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By A. N. Veltmeyer

"INTRODUCTIONTeck-Corona Operating Corporation's David Bell Mine is located 35 Km east of Marathon, Ontario. In conjunction with its 1000 tonne per day gold concentrator, the company operates an effluent treatment plant for the treatment of mill, mine and site effluents prior to environmental discharge. This paper provides a brief overview of treatment strategies and methods, employed to detoxify final effluent.WATER MANAGEMENTThe tailings impoundment basin, located 3 Km south of the plant site, provides storage capacity for all process effluents and site run-off. Basin supernatant (reclaim water) is recirculated to the plant for reuse as process water, in order to minimize fresh water consumption. As site run-off and limited fresh water intake exceed natural losses due to evaporation, reclaim water in excess of process requirements is passed through the effluent treatment (ET) facility to control tailings basin level by providing regulated discharge of environmentally acceptable effluent. (Figure 1)PASSIVE TREATMENTTo reduce treatment costs and burden on the ET facility, reclaim water is fed to the plant to take maximum advantage of natural destruction processes occurring in the tailings basin.These include: volatilizationphotodecompositionbiological oxidation and precipitationstorm water dilutionConcentrator recovery techniques (Figure 2) are directed toward maximizing gold recovery while limiting the addition and extraction of contaminants requiring disposal and eventual treatment.Currently ore ground to 90% -200 mesh is pre-aerated at pH 9.0 with lime for 18 hours prior to 30 hours cyanidation at pH 9.5 with low cyanide ion excess (70 ppm).Pre-aeration passivates cyanicides prior to cyanide contact. This reduces cyanide consumption and the formation of cyanide complexes. In conjunction with recovery requirements low pH is maintained to retard the dissolution of stibnite into its antimony and sulfide components."

Jan 1, 1989

The theme of this conference is æRediscover OtagoÆ. In order to ensure the development and exploitation of mineral discoveries in New Zealand, considerable capital will be required, particularly from overseas. This paper briefly reviews the Government's foreign investment policies and procedures and highlights some trends.

Jan 1, 1992

By G. Roger Miller, Kristine M. Krajnak, Stephen S. Leonard, Stacey Waugh

Repeated exposure to hand-arm vibration through the use of vibrating hand tools can result in the development of the disorder known as hand-arm vibration syndrome (HAVS; (1,3)). One of the hallmark symptoms of HAVS is cold-induced peripheral vasospasms that result in finger blanching (4). Although the vascular and neural pathology associated with vasospasms has been described, little is known about cellular mechanisms leading to this damage (4). To understand how vibration may alter vascular and neural physiology and anatomy, rats were exposed to a single bout of tail vibration and the molecular responses of neural and vascular tissues were measured to determine if there are immediate or sustained affects of vibration that may underlie longer term changes in physiology. Methods Experiment 1. Male Sprague Dawley rats (n = 32, 6 weeks of age) were housed in AAALAC accredited facilities. All procedures were approved by the NIOSH Animal Care and Use Committee and were in compliance with the CDC guidelines for care and use of laboratory animals. Vibration exposures were performed by restraining rats in Broome-style restrainers, and securing their tails to a vibration platform using 6 mm wide straps that were placed over the tail every 3 cm. Restraint control rats were treated in the same manner, except that the tail platform was mounted on isolation blocks and not on a shaker. The vibration exposure was 125 Hz, 49 m/s2, for 4 h. Rats were euthanized with an overdose of pentobarbital (100 mg/kg) 1 h or 24 hours after the exposure. RTqPCR was used to measure transcript levels for endothelin 1 (ET-1), the 3 forms of nitric oxide synthetase (NOS) NOS-1, NOS-2, NOS-3 and norepinephrine receptor subtypes 1D, 2A, 2C, in artery tissue, and to measure calcitonin gene-related peptide (CGRP) and nitric oxide synthase-1 (NOS-1) in ventral nerves. Data were analyzed using 2-way ANOVAs. Experiment 2. Male Sprague Dawley rats (n =24, 6 weeks of age) were maintained as described above. Animals were exposed to a single bout of restraint or vibration. Another group of animals served as cage controls. All animals were euthanized 24 h after the exposure, and tail arteries were isolated and frozen. Reactive oxygen species ROS) were measured using electron spin resonance spectroscopy (ESR). Arteries were homogenized over ice in 1 ml of PBS with protease inhibitor cocktail, using a tissue tearer (Biospecs Products Inc. Racine, WI USA). The sample was split into two 0.5 ml samples. One set had PBS and the spin label hydroxyl-TEMPO [0.1 mM] added while the other set had hydroxyl-TEMPO [1.0 mM] plus the specific hydroxyl radical scavenger, dimethylthiourea (DMTU), added to confirm the presence of the hydroxyl radical. Samples were vortexed and then placed in a flat cell for ESR analysis. The ESR spectrometer settings were: receiver gain, 6.32 x 102; time constant, 0.02 s; modulation amplitude, 1.0 G; scan time, 20 sec; magnetic field, 3490 ± 100 G (2). Data were analyzed using 1-way ANOVAs.

Jan 6, 2006

By Joel Lööw, Jan Johansson, Lena Abrahamsson

Industry 4.0 offers new possibilities to combine increased productivity with stimulating workplaces in a good work environment. Used correctly, digitalization can create attractive jobs in safe control room environments, which provide space for the employee’s full expertise and creativity. This is true also for the mining industry. But, to succeed, it is important to analyze the development from a worker’s perspective. What will happen to their work? What skills will be needed in the mine of tomorrow? We must also consider the risks, such as privacy issues, increased stress, and work-life boundaries. These questions must be understood if we are to create workplaces that can attract a young and diverse workforce to tomorrow’s mining industry. In this article, we try to illustrate what the new technology can mean for the individual miners. We formulate the notion of Mining 4.0 (Industry 4.0 in the mining industry), where we try to create an image of how the future might look from a miner’s perspective and how mining companies may navigate their way to a future that works for all miners. To illustrate the range of possible outcomes, we formulate two scenarios: one utopian and one dystopic. At the end of our article, we bring forward six recommendations that can be considered a beginning of a road map for the human side of Mining 4.0.

By Joel Lööw, Jan Johansson, Lena Abrahamsson

Industry 4.0 offers new possibilities to combine increased productivity with stimulating workplaces in a good work environment. Used correctly, digitalization can create attractive jobs in safe control room environments, which provide space for the employee’s full expertise and creativity. This is true also for the mining industry. But, to succeed, it is important to analyze the development from a worker’s perspective. What will happen to their work? What skills will be needed in the mine of tomorrow? We must also consider the risks, such as privacy issues, increased stress, and work-life boundaries. These questions must be understood if we are to create workplaces that can attract a young and diverse workforce to tomorrow’s mining industry. In this article, we try to illustrate what the new technology can mean for the individual miners. We formulate the notion of Mining 4.0 (Industry 4.0 in the mining industry), where we try to create an image of how the future might look from a miner’s perspective and how mining companies may navigate their way to a future that works for all miners. To illustrate the range of possible outcomes, we formulate two scenarios: one utopian and one dystopic. At the end of our article, we bring forward six recommendations that can be considered a beginning of a road map for the human side of Mining 4.0.

Despite the current economic downturn that is now decimating iron ore production, Minnesota?s mining operators remain optimistic about the long-term prospects for the industry. Reflecting this optimism, the development of several new mining projects continues in the state. The future of mining in Minnesota was the featured topic at the combined 82nd Annual Minnesota Section of SME Meeting and 70th Annual University of Minnesota Mining Symposium. More than 500 mining industry professionals, including engineers, executives, mining managers and equipment suppliers from the around the world, attended the meeting, which was held April 14 and 15, 2009, in Duluth, MN. The combined meeting featured a keynote session with three distinguished speakers plus a panel discussion by representatives from several of Minnesota?s taconite producers. The keynote speakers were Curtis Clark, president and chief operating officer, Behr Dolbear, who gave a presentation on the ?State of the Mining Industry.? Phil Newman, chief operating officer, CRU Strategies, spoke about challenges facing the mining industry and James A. Skurla, acting director, Bureau of Business and Economic Research, Labovitz School of Business and Economics, University of Minnesota Duluth, discussed the importance of mining to northeastern Minnesota?s economy. The taconite producers panel discussion included Jonathan Holmes, vice president and operations manager, ArcelorMittal; Ed Latendresse, vice president and general manger, Hibbing Taconite; John Tuomi, vice president operations services, United Taconite and Mike Mliner, vice president and general manager, Northshore Mining. The mangers provided updates on their respective operation The meeting included concurrent technical papers sessions on mining, processing, environmental and nonferrous mining. The sessions included technical papers that provided information on the status of a number of new mining projects in the state. The conference also offered a SME short course titled ?The basics of iron mining.? A tradeshow that featured about 100 companies and organizations offering products and services to Minnesota?s mining industry ran in conjunction to the conference. It was estimated that more than 900 people, including conference registrants and special invited guests of the vendors, attended the tradeshow opening reception. This was the largest trade show in many years. The Minnesota Section of SME also held its annual business meeting during the conference.

Jan 1, 2009

By R. A. Westin

[Polychlorinated biphenyls (PCR's) have been widely utilised as fire-resistant dielectric coolants; in electrical equipment used in mining applicants, including transformers, capacitors, electric motors, and electromagnets. In addition, PCB's have been used in hydraulic fluids and heat-transfer fluids and are present in many oil-filled transformers. The U.S. Environmental Protection Agency (EPA) recently banned the manufacture of PCB's and equipment using PCB's, and imposed strict requirements on the continued use and disposal of existing PCB equipment. This manual discusses the EPA requirements, suggests ways to decrease the risks resulting from continued use of PCR equipment, and surveys the non-PCB equipment that is available as replacements for the PCB electrical equipment presently used in mines.]

Jan 1, 1980

By Steven W. Schmauch

The U.S. Bureau of Hines conducted e mineral resource survey of approximately 232,000 acres in part of the Humboldt National Forest, Nevada, during 1989. About 7S percent of the study area was covered with mining claims. About 1,800 samples were collected end analyzed for 16 elements. Geologic structure, including thrust faults, is the most important factor in the localization of mineral deposits in the study area. The Independence mine (formerly Jerritt Canyon), Big Springs, and Wood Gulch are the most well known active properties, all developed on large, low-grade, disseminated gold deposits. These deposits have produced almost 3 million ounces of gold and are known to contain more than 8 million ounces of gold. At least 10 barite deposits in the south end of the range have had significant past production and contain 0.2 million tons of resources. Numerous precious and base metal targets have been identified and in some cases quantified during this study.

Jan 1, 1992

By P. K. Leung, S. R. Allada, P. M. Dranchuk, D. Quon

The alternating direction explicit procedure (ADEP) makes use of the boundary conditions to reduce multi-dimensional problems to a series of one-dimensional problems. The method, previously applied to reservoirs containing only an under-saturated oil, has now been extended to cover the case of natural gas reservoirs. l his involves solving a non-linear partial differential equation, application of the procedure is straightforward and no calcuIational problems were encountered. INTRODUCTION There has been a growing interest in formulating mathematical models of petroleum and natural gas reservoirs — models which permit the engineer to examine and evaluate the physical and economic consequences of various alternative production policies. The tremendous reduction in the cost of solving such models in recent years has made possible their use as an almost routine management tool. This reduction is the result not only of improved computer hardware but also of the development of more efficient mathematical techniques. The present paper is concerned with the application of a recently proposed numerical method (ADEP) to two-dimensional gas reservoirs. STATEMENT OF THE PROBLEM Given a two-dimensional Region R, bounded by a closed Curve C (Fig. 1) such that the behavior on Curve C is known, the differential mass balance for each fluid phase in R, neglecting gravitational effects and assuming Darcy's law for fluid transport, can be written as:

Jan 1, 1967

By Onuralp Yücel, Süheyla Aydin, Erçin Ersundu

Turkish iron and steel sector, the base of which was established in the 1930?s, plays an important role in the industrialization and development of the country?s economy. In Türkiye this sector is the major consumer of ferroalloys. There had been a great improvement in Turkish Iron and Steel industry, especially after the 1980?sand as a result, 20.9 million tons of yearly crude steel production placed Türkiye 11th in the global steel output and 3rd in Europe. 15 % of steel produced in Türkiye is flat products, while the long products make the rest. The product composition and the general characteristics of steel production process led to an increase in ferroalloy consumption. Domestically consumed ferroalloys are especially ferromanganese, silicomanganese, and ferrosilicon. As of today, ferroalloy production capacity of Türkiye is 173,800 tons/year; 161,500 tons of which is ferrochrome with high and low carbon grades, 7,300 tons of ferrosilicochrome and the rest is ferrosilicon (5,000 tons/year). Türkiye is one of leading ferrochrome producers in the world considering the above mentioned production figures. However, this production is mainly exported since Türkiye?s stainless steel production level is modest requiring low amounts of ferrochrome. The products of iron and steel industry in Türkiye require large quantities of other ferroalloys, which make Türkiye a major importer and exporter of ferroalloys. The aim of this work is to present production, consumption, import and export quantities of: ferrochrome, ferromanganese, ferrosilicon, ferromolybdenum, ferrotungsten, ferrotitanium and ferrovanadium of Türkiye, between 1990 and 2006.

Jan 1, 2007

By Luke Erickson

San Francisco Public Utilities Commission is planning to replace 5 miles of pipeline under San Francisco Bay. The tunnel will be constructed using an Earth Pressure Balance (EPB) TBM and will be the first TBM-driven tunnel under the Bay. The alignment passes under environmentally sensitive habitats, through interbedded layers of sands and clays, and through a buried bedrock ridge. This paper discusses the geotechnical characterization and anticipated tunneling conditions and presents the analysis of various construction methods that resulted in the selection of an EPB TBM. Considerations related to tunneling with an EPB TBM are described in detail, including ground conditioners, TBM cutterhead wear, muck control, and squeezing ground.

Jan 1, 2008

By B. Jago

From the perspective of metallurgical processing, gold ores can be classified into freemilling and refractory ores. Their extractive metallurgy is largely driven by mineralogical factors such as gold particle size, association with other minerals, coatings and rimmings, presence of cyanicides, oxygen consumers and preg-robbers, presence of refractory gold minerals, and invisible gold in sulphide and sulpharsenide minerals. Gold process mineralogy helps address issues and problems related to gold ore processing. It is widely used as a predictive and trouble-shooting tool in gold ore processing, and provides useful information on process selection, flowsheet development, recovery improvement, and reagent consumption optimization. By combining classic mineralogical techniques, modern instrumental analysis, and diagnostic metallurgy, the mineralogist is able to balance the various types of gold occurrence in an ore.

Jan 1, 2006

Jan 1, 1997

Ground support audits are sometimes necessary in ageing underground mines. Usually, the purpose of such audits is to assess the state of the ground support in various parts of the mine, identify areas that require attention and establish rehabilitation requirements. In 2005, Brunswick Mine, located in Bathurst, New Brunswick, Canada, completed a comprehensive mine-wide ground support audit. The areas examined included excavations in several mining blocks, as well as ramps, shaft stations, garages, shops, etc., throughout the mine. A vast amount of data was collected over a period of two weeks by multiple auditing teams. The audit was followed by a data digitisation exercise, and the creation of a data management system to store audit results and keep track of subsequent rehabilitation activities as they occur. One aspect of the data management system was the incorporation of a function for reporting on ground rehabilitation progress, along with the capability of updating mine level plans for easy visual presentation of this progress. This article describes the approach implemented at the mine to carry-out the audit, as well as the database constructed to manage the results.

May 1, 2009

By Greenwood J. N

This work was commenced at a time when information on the manufacture of cemented tungsten carbide was urgently needed in Australia. Much information of a general type has been published, but many of the details of the processes used are still undisclosed. The aim of this research was to determine a satisfactory way in which cemented tungsten carbide could, be made, and to investigate the problems which are associated with the process. As the work proceeded, its ramifications grew continually, and it was necessary to limit the possible lines of investigation. After much experimental work, a 9% cobalt-tungsten carbide alloy was developed which had satisfactory properties when used as a cutting tip. The effect of certain variables on the properties of this particular alloy was investigated.The tungsten carbide was prepared in stages from King Island scheelite concentrates under strict laboratory control, whilst the cobalt (1) used was made from cobalt oxide prepared from crude cobalt oxide obtained from Eisdon.In order to clarify the detailed experimental work, a brief summary of the method used for the preparation of cemented tungsten carbide follows.Tungsten carbide and cobalt are prepared in a very finely powdered state, and are then thor,oughly mixed by a ball milling operation. The resultant mixture is pressed in a suitably shaped die into small compacts which are subsequently '''presintered,'' i.e., heated' in hydrogen between 800°C. and 1000°C. The final sintering is carried out in hydrogen between 1,400°C.and 1,600°C. for about half an hour. These "alloys" may contain from 3 to 13% cobalt, depending on the particular properties required of them.PREPARATION OF MATERIALSThe tungsten oxide prepared as described by Smithells (2) was extremely finely divided, and after a few hours' grinding in a ball mill, the powder consisted of material below 10 microns iJ;l size. The oxide was reduced to tungsten metal with hydrogen in a tube furnace. The reduction was carried out at 800-900° C., a rapid flow of hydrogen being maintained in order to remove the water vapour' formed as a result of the reactions:

Jan 1, 1942

By Gray Mullins

The construction of drilled shafts as well as other cast in place foundation alternatives relies heavily on good practices from the contractor, engineer, and inspector in order to produce a quality foundation element. As many of the installation methods involve blind concreting processes, it is difficult to be certain of an intact concrete mass of the intended dimensions. A new integrity test has been developed that provides additional insight into the integrity of drilled shaft concrete. By measuring the temperature throughout the shaft via standard access tubes, the measured temperature profile can be compared to the normal signature associated with a shaft of the specified size. This article provides an overview of the new method development, test procedure, analysis, and results.

Jan 1, 2010

By Rodolfo Espinosa

"Industrias Peñoles, S.A. de C.V. in Mexico, has nine mining operations, six managed by Peñoles (base metal mines) and three managed by Fresnillo plc (precious metal mines). Seven of the operations use flotation and the other two are heap leach operations, one for gold and the other one for copper.This paper gives a brief introduction of Peñoles, shows mine locations and describes the main process characteristics of each concentrator. It also presents four of the new operating practices that were implemented over the last four years to improve the economics of the mining operations. These include (1) the use of centrifugal gravity concentrators to increase the recovery of gravity recoverable gold (GRG) and silver (GRS), (2) the use of expert systems to reduce process variability while increasing grades and recoveries, (3) the application of the Six Sigma methodology to key projects to ensure success and personnel development and (4) the use of water chemistry fundamentals to identify chemistry problems and design adequate solutions for improving grades and recoveries.INTRODUCTIONPeñoles was founded in 1887. It is a mining group with integrated smelting, refining and chemicals producing operations. Peñoles is the world largest producer of refined silver and metallic bismuth, the leading Latin American producer of refined gold and lead. It is amongst the world leading producers of refined zinc and sodium sulfate.Peñoles operates and controls six underground mines in Mexico and is the largest producer of zinc and lead of the country. It also produces copper concentrates and cathodes. Through its 77.1% equity stake in Fresnillo plc (a London Stock Exchange listed company); Peñoles is also a significant producer of gold and silver. Fresnillo plc operates three precious metal mines in Mexico. While Fresnillo is the world largest primary silver mine, Ciénega and Herradura are two leading gold mines of Mexico. Figure 1 shows a map of Mexico indicating the locations of the Peñoles mines. The main process characteristics of each concentrator are listed in Table 1."

Jan 1, 2011

By Tim O’Neil

“America’s mining industry brings good jobs to communities across America and provides the energy, minerals and equipment that are vital to our economic security and our way of life.” That was the surprise videotaped greeting from President George Bush at the official opening ceremony of MINExpo 2004in the Las Vegas, NV Convention Center. Jack Gerard reinforced the upbeat mood at MIN-Expo. He praised Nevada Gov. Kenny Guinn for his support of the mining industry, the state’s largest manufacturing sector. Gerard is the president and chief executive officer of the National Mining Association, the sponsor of MINExpo 2004.

Jan 1, 2004

By Charles E. Whieldon

The importance of producing more oil from known petroleum reserves has placed increased emphasis on the application of secondary-recovery methods. Recently published reports3 4/ describe the results of waterflooding in Roane and Pleasants Counties, W. Va. (see fig. 1.) This report describes the Barron Kidd Oil Co.?s Santee waterflood project, Maxton sand, Burton field, Church district, Wetzel County, W. Va. (See fig. 2.) The Federal Bureau of Mines hopes that these reports will stimulate interest in improved waterflooding techniques, thereby discouraging premature abandonment of oil leases.

Jan 1, 1961

By W. J. Theron

The purpose of the paper is to give an introduction to the concept of fatigue and its causes in the mining industry. By knowing the fundamental role it plays, together with its dynamics, can positively contribute to a mine?s safety management system. The difference between physical and psychological fatigue will be addressed with a possible range of causes that could trigger fatigue. There are two main sources of fatigue: firstly, work-related fatigue which is associated with activities at the workplace; and secondly non-work-related fatigue. The shared responsibility between the employer and employee is also discussed as it involves factors that occur both in and outside the workplace. Employers have the responsibility to manage fatigue through using a risk management approach. Employees have the responsibility to ensure they get enough sleep, take sufficient and regular nutrition, are healthy and physically fit and come to work fresh and alert. The impact of the implementation of a fatigue management plan and procedures has the potential to eliminate employee fatigue or its causes, reduce the likelihood of fatigue occurring in the workplace, and counteract the effects of fatigue when it occurs. Factors considered when implementing a fatigue management system include: extended hours of work, shift work, time of day and work design. Fatigue is one of the major role players (either causal or contributory) when it comes to causes of fatalities in the mining industry. Our main challenge in identifying whether fatigue played a role is the fact that it cannot be tested in post-mortems like drug or alcohol abuse. It is an aspect worth understanding and getting an organization sensitive to managing it properly to benefit both organizational as well as employee needs. Keywords Signs of fatigue: Causes of fatigue, circadian rhythms, the fatigue equation, fatigue management, fatigue affecting safety, fatigue fighting tips, lifestyle suggestions.

Jan 1, 2011