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By R. Mckinstry, M. Rantapaa, T. Bolles

"Measurable improvements in throughput have been documented at Barrick Goldstrike due to increased ore fragmentation through efficient drilling and blasting techniques. A decrease in throughput at the autoclave, due to increasingly hard ore, was identified in early 2002. A team of individuals from the open pit and process areas worked closely on the Drill-to-Mill (D2M) Continuous Improvement initiative to ensure that it would address the needs of both groups, with the target of actually improving throughput in future years, despite the projected harder ores. A series of tests were conducted to determine if adjustments to drilling and blasting could positively influence throughput.Better fragmentation and a subsequent increase in mill throughput were achieved through the use of electronic caps for more precision and flexibility, as well as for allowing extremely fast shots; explosives with a higher velocity of detonation (VOD) to provide for improved shock energy; and improved distribution of the explosives by decreasing pattern spacing. Early tests indicated a significant increase in throughput when processing identified harder ore. It is anticipated that the total process throughput (hard and soft ore) will increase by 6 tph in 2003 due to the improved fragmentation of the hard ore.Barrick Goldstrike’s D2M initiative includes roaster hard ore (BWI>17), as well as autoclave hard ore (BWI>15). Approximately 6 million tons of D2M material were shot in 2003, a relatively small amount compared to the 150 million tons to be mined. The benefit of additional ounces produced should far outweigh the additional drilling and blasting costs."

Jan 1, 2005

By R. A. Cattell

Continuing progress in a petroleum and natural gas research program of world-wide significance makes it difficult to pinpoint accomplishments within definite time limits, and it is helpful to look back as well as forward in attempting to introduce and summarize the petroleum work of the Bureau of Mines in the fiscal year 1953. The 1952 report2 / indicated progress in a long-range program applicable in large part to both defense and peacetime requirements. The present report indicates a continuation of that program, modified partly by new demands and interests of government and industry, and is highlighted by a number of significant contributions to the knowledge of petroleum and natural gas and their production and utilization. The intent of the program was clearly epitomized in a statement made near the end of the fiscal year at a general conference of Bureau of Mines personnel where the record was critically reviewed:

Jan 1, 1955

By Jewel Andrew Gomes

Arsenic is considered as one of the toxic materials being controlled by Environmental Protection Agencies in several developed and developing countries. It is found in the nature as constituents of the soil, minerals and also in various organic forms. It enters the air, water, and land from wind-blown dust and gets into water from runoff, leaching, soil erosion and anthropogenically from chemicals used for wood preservation, insecticides, medicine, military purpose, pigments, and electronic circuitries. There are several techniques available for removal of Arsenic, such as coagulation/filtration, lime softening, ion exchange, reverse osmosis, nanofiltration, wet chemical, and electrochemical. Electrocoagulation has been found as one of the most efficient techniques to remove inorganic arsenic with more than 99% efficiency. In this paper, we present our work on electrochemical treatment of both the inorganic and organic arsenic from water using various sacrificial electrode materials, i.e., iron, aluminum, copper, and combination of them. The floc produced by this method has been also characterized using XRD, SEM/EDS, FTIR, and cyclic voltammetry.

Jan 1, 2010

By David Harrison, Edward J. Walter, Meitra Ferek

Agreat tool in the prevention of blasting complaints and subsequent damage claims. In today’s highly competitive industry, we are always looking for ways to become more cost effective. This article investigates the importance of pre-blast surveys-not just for regulatory compliance, but as an overall long term cost cutting and public relations tool.

Jan 1, 1995

By Leandro Moraes da Silva Graciotti, Lorenzo Bortolon Scandian

Este artigo tem como premissa apresentar o quadro evolutivo referente a Segurança do Trabalho no Terminal de Produtos Siderúrgicos (TPS) do porto de Praia Mole bem como mostrar as novas ferramentas e tecnologias aplicadas ao processo portuário para garantir a perenidade das operações. Neste documento apresentaremos o Terminal de Produtos Siderúrgicos, sua estrutura de funcionamento, e as operações executadas. Em seguida, explicitaremos as ferramentas de gestão de segurança utilizadas e suas tecnologias. Por fim, exibir-se-á os impactos provenientes dos recursos e ações de segurança executadas, enfatizando a importância da tecnologia em conjunto com a segurança do trabalho no TPS.

Oct 1, 2019

By Elaine T. Cullen

Miners, like many skilled blue-collar workers, are not traditional learners. They have not always been successful in classroom-type settings, preferring to learn on the job in a hands-on environment. U.S. law requires that miners have a minimum of 8 hours of safety training annually, plus 40 hours for underground miners and 24 hours for surface miners when they enter the industry. However, miners rarely view this training time positively. In fact, it has been called “safety jail” by many, who regard it as a time to get a little extra sleep While mining has become far safer in the past 100 years, it is still a dangerous occupation. The Office for Mine Safety and Health Research, a part of the National Institute for Occupational Safety and Health (NIOSH), has funded a project for the past 4 years to address this challenge. The purpose of the research was to find a way to develop effective safety training for these people. Miners are born story tellers. They share “near miss” stories, stories about master miners they have known, and stories about how things used to be. These stories not only pass along information about what will happen if a miner fails to respect the mining environment, they also instruct listeners in the culture of mining and the values that it embraces. Stories, it seems, are a way to get safety messages across to miners, especially inexperienced ones, and using older, wiser miners in these stories is an obvious choice. This paper will discuss how a series of training videos was developed, how “master miners” and story lines were chosen, and how the resulting videos have been received in the mining industry.

By W. G. Sandell, L. C. Bauerle, K. C. Dean

"INTRODUCTION As a part of the wartime activities of the Bureau of Mines, metallurgical services were extended to other Government agncies engaged in purchasing and stock-piling some of the more critical and strategic materials. At the request of Dr. Alan M. Bateman, special representative of the Metals Reserve Company, metallurgical studies were made on three samples of oxide tin ore from, the States of Zacatecas and Guanajuato, Mexico. The samples were submitted for testing by A. Porraz of the Financiera Miners, S. A., institution Financiera, Edificio Guardiola, Despachos 500-507, Mexico, D. F.The samples as received were marked Nos. 1, 2, and 3 and described as follows:Sample 1. - Origin: Mining camp ""El Naranjo,"" municipality of Sombrerete, State of Zacatecas, Mexico. This sample was partly concentrated by washing and as received was all minus 10-mesh in size.Sample 2. - Origin: Deposits in Sierra. Fria and Juan Cherey, municipality, of Jerez,State of Zacatecas, Mexico. This sample represented run of-mine ore.Sample 3. - Origin: Mine ""La Frontere, "" Ranch of San Pedro del loya, State of Guanajuato, Mexico. This run-of-mine sample was low in tin content but came from a highly mineralized tin field."

Jun 1, 1947

By J. J. K. Daemen

Mining Engineering education is in trouble, if not in crisis. The most visible signs are the decrease in the number of programs that offer the degree, and the continued difficulties in attracting students to the discipline. Unless these trends are reversed, the future of the profession is uncertain, at best. Remedies have been proposed, and some are drastic. They range from consolidating mining engineering education into one or two national schools, to cooperative regional programs, to distance education programs, and to proposals to limit mining engineering to a graduate degree or specialization only. These alternatives deserve serious attention and merit discussion. I hope that one alternative that will remain on the table is the classical and traditional “School of Mines”. A reasonable number of such schools are needed to provide the educational diversity and the critical mass to maintain accreditation and professional registration for their graduates. Most importantly, such an approach is most likely to assure the continued existence of mining engineering as a profession. It also provides the best educational framework to teach mining engineers. However, such Schools are vulnerable, highly susceptible to university budget pressures, and probably can survive only with strong external support.

Jan 1, 2004

By J. M. Font, R. G. Reddy

Jan 1, 2004

By Alexander Garcia

Roof and rib falls are the basic ground control hazards associated with underground roadways during development, stand up and, if applicable, retreat. Falls of ground can happen following the deterioration of supports or rock conditions over time, and particularly as a consequence of continuing rock deformation and/ or failure to install adequate support. Once developed, the risk of a failure is increased due to the effects of time as well as to front abutment stresses through retreat mining. The measurement of strata displacement using monitoring equipment is a form of ground control risk assessment. These monitoring systems are active, or ?live?, in a sense that risk is assessed real-time. However, there are circumstances in which falls of ground can occur without the prior recording of excessive movement. In addition, monitoring equipment is typically placed at set intervals, and strata conditions could vary between these points. Consequently, a visual assessment of other factors contributing to the risk of a fall should be made in order to complete a ground control risk assessment. Such surveys are usually one-off, thus capturing roadway conditions at one particular point in time. Ongoing deterioration is not documented through such one-time surveys, and there is a requirement for real-time or live assessment where a system is in place so that observation data can be updated on an ongoing basis, and a useful summary of prevailing roadway states produced on demand. To address the shortfalls of one-time assessments, a ?live? computerbased quantitative ground control risk assessment process has been developed. It combines visual observations processed in a quantitative manner with existing monitoring data into an interpretable output which indicates zones of roadway where there is an increased risk of a fall of ground from the roof or sides, so that remedial action can be carried out to mitigate that risk. Through improved procedures, it is now possible to generate a ground control risk assessment for each roadway, and one which can be updated frequently. This paper aims to outline and describe the assessment process.

Jan 1, 2012

By M. Javier

Defining the concept of sustainability is an important step for industry and society. It is necessary in order to clarify what it means when debunking the many misinterpretations pervasive in different levels of anthropogenic activities. Essentially, the extractive industry has a harvest of differences. Mining involves the extraction of natural resources which are finite, exhaustible, non-renewable, unsustainable, and pay only once. It is remarkable that the definition of sustainability that we will shortly arrive at has totally different characteristics from the definition accepted throughout society. We categorize nature as having its own destiny which is controlled by its own rules and principles and its own society, and is part of nature; therefore, society depends on nature and not vice versa as the initial focus. To society there are no conditions to humanize nature but only respect nature?s rules. It was a challenge to find simplicity for this task not only for the definition but also for the explanation of this concept specifically, to answer the question, ?what is the true meaning of sustainability?? Finally, we are also able through this definition to provide fuel for wide discussions and stimulate critical thinking to improve such a concept. As a result, we present this definition as the tool for society today and for future generations.

Jan 1, 2012

By Frank E. Chase, John L. Ellenberger, Christopher Mark

The nature of competition in the coal market tends to deplete the most favorable coal reserves first, and forces subsequent development of mines in more extreme ground conditions such as those associated with multiple-seam mining. In fact, 70% of the United States coal reserves are in multiple-seam situations. The National Institute for Occupational Safety and Health (NIOSH) is conducting research to develop mine design algorithms that will result in safer multiple seam mines. This paper presents an overview of multiple seam issues in the central Appalachian coalfields. To date, more than 50 case histories have been analyzed from 20 operating mines in Eastern KY, Western VA, and Southern WV. Each case history is classified according to the degree of multiple-seam interaction, ranging from no apparent interaction to severe interaction with direct impacts on mine safety and resource recovery. The case histories are also examined with regard to amount and geologic characteristics of interburden and overburden, and design stability factors. The sequence of mining has also been found to be critical when the lower seam is fully-extracted. This paper compares current case histories to traditional rules of thumb. In addition two situations were modeled using LaModel software. LaModel has been upgraded to import pillar grids and topographic data from AutoCAD files. The cases presented demonstrate vertical stress capabilities of LaModel.

By Kazem Oraee

In underground coal mining, particularly room-and-pillar methods, the coal pillars play a significant role in roof stability. If the pillar dimensions are increased, the pillar bearing capacity also increases, but more coal remains in the pillar and therefore the recovery of mining operation decreases. Therefore, determining the optimum pillar dimension based on technical, economical and performance parameters is important. In this paper, the coal pillar is designed by using the concept of ground reaction curve (GRC). For this purpose, the GRC for coal pillars is drawn and then the elastic and plastic zone of coal pillar behavior is determined. Based on elastic and plastic zone, different equations are presented to draw a pillar reaction curve and the process of coal pillar design based on GRC is explained. As a case study, this new technique is applied to study the coal pillar state in Tabas coal mine of Iran. The results show that the presented new approach is successfully used in the design of the optimum coal pillar dimensions, and also determines the elastic and plastic behavior limit, which is important especially for the logical design of yield pillars.

Jan 1, 2009

By Y Xie, L O’Connor, S C. Dominy

Sheeted vein gold deposits are characterised by multiple subparallel veins and often free milling gold. Variability in gold grade and recovery parameters are enhanced by poorly designed sampling and test work protocols. Poor quality samples generally equate to an enhanced nugget effect. A sample can be described as being representative when it results in acceptable levels of bias and precision. Total sampling variability can be quantified by the relative sampling variance, which measures the total empirical sampling variance influenced by the heterogeneity of the lot being sampled under the current sampling / test work protocol. Effort should be made to minimise the relative sampling variance through Theory of Sampling (TOS) and quality assurance / quality control (QA/QC) application. This contribution reports on a case study that exemplifies how high-quality grade and recovery data can be gained from a well-designed and planned drilling, sampling and test work program, followed by bulk sampling. Results across historical resource drilling, geometallurgical drilling, laboratory assay / test work, geometallurgical modelling and a bulk sampling/pilot processing study are reconciled. A whole core, entire-sample test work protocol was used to acquire fit-for-purpose gold grade and recovery data for inclusion into a Pre Feasibility Study reported in accordance with the JORC Code.CITATION:Dominy, S C, O’Connor, L, Xie, Y and Glass, H J, 2017. Geometallurgical sampling protocol validation by bulk sampling in a sheeted vein gold deposit, in Proceedings Eighth World Conference on Sampling and Blending , pp 185–196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By M. Moys

The use of temperature measurements for unusual applications in the analysis and control of column flotation and milling is discussed. This is followed by a review of some of the authors current research in the application of the discrete element method to the modelling of particulate processes, specifically milling, fluidized beds and chute flow.

Jan 1, 2005

By Robert B. Hopler

Explosives, originally used only in fireworks and warfare, became legitimate contributors to human progress when miners in Eastern Europe began using them to break rock in the early 1600%. Since that time these powerful materials have had a dual role in the world: as agents of destruction in war, and as irreplaceable tools necessary to advance civilization. In the latter role, they serve as agents to enable mankind to produce metals, build roads, and drive tunnels. In other words, to provide those materials, services, and infrastructure without which the modern world could not exist.

Jan 1, 1997

By G. A. Kosick, G. S. Dobby, O. Matwijenko

"A 100 kg/hr portable flotation pilot plant has been operated at Kidd Creek Mines with the objectives of:(a) determining performance expected by column flotation circuits on primary zinc and copper cleaning, and (b) evaluating column flotation circuit configurations.The self-supporting pilot plant, owned by Minnovex Technologies Inc. and operated by Minnovex and the University of Toronto, consisted of three 16 cm diameter by 6.5 m high columns and a bank of four Denver No. 7 cells. It was configurable to any arrangement using these four (or fewer) units. The columns were controlled through the use of multiple pressure transducer measurements. This paper presents the approach to testing and the results of more than 70 circuit tests. INTRODUCTIONThe integration and retrofitting of flotation columns within existing mechanical cell flotation circuits is becoming a common occurrence. The correct approach to this integration, however, is often difficult to define, due to a scarcity of previous experience and the difficulty in predicting column circuit performance. In most cases, the effect of column implementation has been experimentally assessed using a single pilot column, with the consequence that selection of an appropriate circuit to implement is difficult. Important considerations are the impact that column water addition will have on the existing operations, and the differences between mechanical cell and column performance in integrated cleaning circuits.To address the problem of circuit selection a portable flotation pilot plant, consisting of both columns and mechanical cells, was designed and constructed by Minnovex Technologies. The pilot plant was structured for complete flexibility of circuit configuration, with the intent to provide a means by which both research and plant personnel could determine the best possible column circuit configuration for a given application."

Jan 1, 1990

By Thierry Bernard, Jean Marc Laboz

This paper explains why and how integration of EIS (Electronic Initiation System) with dedicated software tools can increase benefits to blasters and at the same time simplify the design of blast sequence

Jan 1, 2000

By Timothy R. Eby

"The Wabush Mines project was formed in 1956 to develop a large iron ore property in Western Labrador. The town of Wabush along with the mining and concentrating facilities are located 640 air miles from Montreal, and 734 air miles from St. John's. The operation has been in production since late 1964.While mining and concentrating operations are located in Labrador, the pelletizing facilities are situated 275 miles south at Sept-Iles, Quebec. Dedicated in 1965, Wabush produces six million tons of high quality iron ore pellets annually. The company employs 1, 550 people at Wabush and the Pointe Noire plant at Sept-Iles.Wabush Mines is an unincorporated joint venture of three companies -The Steel Company of Canada, Dominion Foundries and Steel Ltd. and the remaining 58% by the Wabush Iron Co. Ltd. Wabush Iron Co. Ltd. is in turn owned by six companies: The Youngstown Sheet & Tube Company, Inland Steel Company, Interlake Inc., Wheeling Pittsburg Steel Company, Finsider International S.A. and Pickands Mather & Company which is also managing agent.The town of Wabush is set in a remote part of Northern Canada accessible only by rail and air transportation. But this in no way has hindered the growth and development of the area. Modern housing units, shopping facilities, airport and of course, recreational facilities are all patt of every day living amenities, an accepted aprt of southern communities, but quite unique for northern isolated mining localities."

Jan 1, 1978

By M Lentz

This paper will discuss the issues associated with blasting in an urban mining environment that have been addressed by Winstone Aggregates at the Mt Wellington Quarry. These issues include - control of vibration and air overpressure, repeatability of shot performance, fragmentation on an extremely low maximum instantaneous charge, compliance with Territorial Authority regulations and perception. Over the last two years, in order to address these issues, Winstone Aggregates have undertaken a programme of continuous improvement, which has included; ò implementation of new technology; ò revising site procedures; ò conducting an investigation into the structural response of local buildings; ò investigating safe extrapolation; ò extensive public consultation; ò establishing credibility during the consent process; ò identification of perception issues; and ò building relationships and trust with neighbours. The issues addressed at the Mt Wellington Quarry have increasing significance for traditionally rural mining operations, as the input of the local community being urban or rural, increases. New and existing operations have the potential to adopt best practice now, building trust with the community and raising the profile of the industry.  

Jan 1, 1999