Search Documents

By Crazy Horse - The Journal of Explosives Engineering - Vol 20 No 1

The crew at Crazy Horse Memorial has produced a w o n d e rful new video called “The Fine Art of Mountain Carving.” The video closely examines for the first time, the extraordinary explosives engineering on the Crazy Horse mountain currently in pro g ress in the Black Hills of South Dakota. The 56-minute video takes the viewer up the mountain for a behind-the-scenes look at the drilling and blasting crew at work on the mountain. The video was written, edited and produced by Robb D e Wall and is available exclusively from the Crazy Horse Memorial in both DVD and VHS formats. For i n f o rmation, see www.crazyhorsememorial.org The following, is a brief summary of the 25 steps involved in carving the mountain. The video goes into extensive detail on each of the 25 steps. Both those in the explosives industry and those outside the industry will find the video intere s t i n g .

Jan 1, 2004

By Justo G. Ramón Rojas

Con la promulgación de la Ley peruana de seguridad y salud en el trabajo, Ley 29783, desde hace cinco años, el objetivo primordial de todas las empresas mineras, fue actuar en pro de su cumplimiento, implantar nuevas estrategias para prevenir situaciones que hasta entonces no se había considerado como factores de riesgo. En definitiva, la preocupación del Estado se centró fundamentalmente, en “que” debíamos hacer para mejorar el desempeño de la seguridad laboral en la búsqueda de mejores condiciones de trabajo.

Sep 1, 2017

AustraliaÆs strong position as an aluminium producer and potential magnesium producer combined with rapid market growth in the automotive industry, proximity to Asia and other natural advantages points to considerable opportunity for downstream processing and manufacture with light metals in this country. Development of a vertically integrated light metals industry in Australia needs to be pursued with vigour, as does the continued development of global strategic alliances through the value adding chain.

Jan 1, 2000

By I. Nimmo

Since the beginning of Aluminum mining and refining the industry has lived with distributed control rooms and suffered from many behavioral problems common with this design. When Human Factor/Ergonomic design is introduced to a Western Australian installation a common centralized control room realized many improvements including economic payback. Communications issues were resolved, better coordination of materials, improved situation awareness during startups, abnormal operations and an opportunity to make improvements during normal operations characterize the changes at the Worsley Refinery. This presentation will review the reasons for the change. Since the beginning of Aluminum mining and refining the industry has lived with distributed control rooms and suffered from many behavioral problems common with this design. When Human Factor/Ergonomic design is introduced to a Western Australian installation a common centralized control room realized many improvements including economic payback. This presentation will review the reasons for the change, what changed and the process of changing the culture from reactive to predictive and what difference that has made.

Jan 1, 2011

By Milford L. Skow

This report summarizes the principal activities and results of 15 years of research by the Bureau of Mines, U.S. Department of the Interior, on methane control in coal mines. This research has investigated fundamental factors regarding the occurrence and movement of methane in coal beds, removal of methane prior to mining, and control of methane during mining. The report includes a bibliography listing the more than 150 publications resulting from the Bureau's methane control program as well as numerous other references, a section on methane recovery and use, a look at the upcoming Bureau of Mines research program, and a brief review of methane drainage practices in other coal-producing countries.

Jan 1, 1980

By Steve Lalancette

Centre Jardin Lac Pelletier (CJLP) has been a leading actor in the revitalisation of closed mining sites in northern Québec for over 20 years. Over that period, CJLP developed a cost-efficient technique that transforms sterile mining residue into a substrate able to support a resilient ecosystem. Using a unique mix of organic matter, fertilisers and selected plant species, this technique rapidly builds a microorganic fauna and a layer of humus that will sustain the creation of vegetation coverage. The coverage is composed of over 13 different plant species, each having a unique role in the development of a resilient ecosystem, from soil stabilisation to nitrogen fixing. Considerably less expensive than traditional methods using civil engineering techniques, it does not require the use of heavy machinery or the spread of topsoil. This technique has been successfully used to restore over 20 sites in Québec such as Joutel, Yvan Vézina and Louvicourt. It is a proven technique that has passed the test of actual implementation. The presentation will review the biological, production and economic aspects of the technique through the revitalisation of the Joutel site.

May 1, 2011

By S. D. Botts, F. Cantuarias

"The Antamina project, owned by BHP Billiton Plc, Mitsubishi Corporation, Noranda Inc., and Teck Cominco Ltd., is a $2.3 billion copper/ zinc project, located in the Ancash Department of Peru. The project consists of an open pit mine, a 70 000 ton per day concentrator, a 302 km long concentrate pipeline, port facilities, a new access road, power line, and town site. The project is designed to produce up to 1.5 Mtpy of copper and zinc concentrates over a 23 year project life, and will be the third largest producer of zinc and the seventh largest producer of copper in the world.This mega project is the largest mining investment in the country and, during its construction stage, was the most important construction project worldwide. On May 28, 2001, Antamina commenced testing operations and four months later, it reached commercial production. Antamina was officially inaugurated on November 14, 2001 by Peruvian president Alejandro Toledo.The construction stage of the project generated 8000 direct jobs, with a peak of 10 000 employees, and 30 000 indirect jobs. The permanent workforce consists of approximately 1650 employees, the vast majority of which are Peruvian Nationals, around 30% of whom came from the region where the deposit is located. Approximately 5600 indirect jobs were generated from the project. Independent sources state that Antamina increased the Peruvian mining exports by 30% (mining exports constitute 50% of Peru’s total exports) and Peruvian GDP by 1% in its first year of full operation in 2002.Since winning the privatization bid for the project in 1996, the company has implemented an approach to community development and environmental protection based on sustainable development principals. Throughout the development of the project, a number of initiatives have been undertaken to ensure full involvement of the local populations in community development activities and the company’s environmental program.Due to its size, difficult logistics, cultural considerations and financial aspects, the project has faced a number of unique challenges in the area of environmental protection and management of community interaction. Antamina has been innovative in its approach to these issues and, as a result, has set new standards in Peru for environmental and community management and sustainable development."

Jan 1, 2003

By Steven D. Botts

The Antamina project, owned by BHP Billiton Plc, Mitsubishi Corporation, Noranda Inc., and Teck Cominco Ltd. , is a $2.3 billion copper/zinc project, located in the Ancash Department in Perú. The project consists of an open pit mine, a 70,000 ton per day concentrator, a 302 Km. long concentrate pipeline, port facilities, a new access road, power line, and town site. The project is designed to produce up to 1.5 million tonnes per year of copper and zinc concentrates over a 23-year project life, and will be the third largest producer of zinc and the seventh largest producer of copper in the world. This mega project is the largest mining investment in the country and, during its construction stage, was the most important construction project worldwide. On May 28th, 2001, Antamina commenced testing operations and four months later, it reached commercial production. Antamina was officially inaugurated on November 14th, 2001 by Peruvian president Alejandro Toledo. The construction stage of the project generated 8,000 direct jobs, with a peak of 10,000 employees, and 30,000 indirect jobs. The permanent workforce consists of approximately 1650 employees, the vast majority of which are Peruvian Nationals; around 30% of whom came from the department of Ancash where the deposit is located. Approximately 5,800 indirect jobs will be generated from the project. Independent sources state that Antamina will increase the Peruvian mining exports by 30% and Peruvian GDP by 1.4% within its first year of full operation in 2002. Since winning the privatization bid for the project in 1996, the company has implemented a successful approach to community development and environmental protection based on sustainable development principals. Throughout the development of the project, a number of initiatives have been undertaken to ensure full involvement of the local populations in community development activities and the company?s environmental program. Due to its size, difficult logistics, cultural considerations and financial aspects, the project has faced a number of unique challenges in the area of environmental protection and management of community interaction. Antamina has been innovative in its approach to these issues, and as a result, has set new standards in Perú for environmental and community management, and sustainable development.

May 1, 2002

Creating Value and Improving Environmental Performance by the Recovery of Valuable Products from Tailings from the Athabasca Oil Sands in Alberta, Canada

Sep 13, 2010

By John E. Tilton

The ability of companies and countries to mine copper and other mineral commodities competitively and in the process to generate new wealth depends on their mineral endowment. Chile, for example, produces and exports copper because it is well endowed with high-quality, low-cost deposits. This production creates wealth that benefits mining companies and their stockholders, the government, local communities, as well as copper consumers around the world. The widespread perception that mineral endowment must largely determine competitiveness, or what economists call comparative advantage, must be true at any particularly moment. Countries with abundant reserves must be competitive. This follows from the definition of reserves — the quantity of a mineral commodity found in discovered deposits that are profitable to exploit under current conditions. As a result, it is a tautology and not particularly interesting. The important question is what causes reserves to change over time, producing in the process new wealth and shifts in competitiveness?

Jan 1, 2003

By M. J. Blattman

Upon completion of an underground mine design, the planning engineer is faced with a surprisingly complex problem, “What development and mining sequence should be implemented so as to maximize the return on investment?” The problem relates to the scheduling of development headings to access stope production areas in such a way that the most money is made as quickly as possible for as long as possible. The total dollar value of the stopes, the average grade, the total tonnage, nor even the profit margin do not accurately give an indication of the “proper” mining sequence on their own. This paper will outline a method being developed by the author that can create a sequence of events that maximizes the net present value (NPV) of a given development and production design using information already being generated during the design process.

Jan 1, 2003

By Mark P. Juzli

During the 1980s, a revolution has been taking place in industrial minerals marketing. Transportation deregulation and a handful of creative marketing and distribution managers have completely changed the rules for marketing many industrial minerals. Minerals are being transported much farther than in prior decades and at much less cost. Bulk and package terminals are becoming increasingly common as a means to take advantage of freight rate savings and to provide enhanced service to faraway customers. Water and rail transportation are being used increasingly to penetrate markets considered unreachable just a few years ago. No longer do the textbook rules of thumb for industrial minerals marketing apply. This author recalls three of those rules he was taught in mineral economics graduate school in the 1970s. As recorded in class notes: • construction aggregates are seldom shipped more than 32 km (20 miles) from the quarry; • cement is sold within 240 km (150 miles) of the mill; and • industrial sand is sold regionally - it is freight constrained to a market radius of no more than 320 to 400 km (200 to 250 miles) from the plant. And yet, the author looks up in 1989 and observes overland movements of aggregates of many hundred miles, overland movements of cement and industrial sand of 1600 km (1000 miles) or more, and water movements of both aggregates and cement into the United States from sources halfway around the world. Truly, industrial minerals are in the midst of a marketing revolution. The companies that have led this revolution have enjoyed considerable financial success in the 1980s. They have enhanced their profitability by increasing market share, capacity utilization, and average selling prices by taking product to remote markets where premium prices are available. They have consistently outperformed their competition, many of whom remain unaware that the marketing revolution going on around them is actually a transportation/distribution revolution. The successful industrial minerals company of the next 10 to 15 years must participate in the transportation revolution as it continues to evolve. Additional human and capital resources must be committed to maximize the effectiveness of a company's transportation and

Jan 1, 1989

By R. H. Schonewille

One of the many challenges in developing new metallurgical processes is choosing the best option for validating process design parameters and establishing the process operating window. Historically this has been achieved by constructing pilot or demonstration plants of considerable size and complexity, to enable integrated operation of all key process units for a significant duration. While this would appear to be the best option for minimizing technical risk, it is often impractical from a perspective of cost, schedule, resources or bulk sample acquisition. Such an undertaking can even provide a false sense of security, as the optics of running a complete scaled-down version of a commercial plant suggest a high level of process understanding, regardless of the challenges encountered during operation. Xstrata Nickel has undertaken numerous process development and improvement projects over the past 15 years to support green field project development and continuous improvement in existing operations. The approaches used have included; computer simulation, cold flow modeling, construction of pilot test units in third party facilities, commercial plant referencing and the more conventional construction of integrated test plants. Regardless of the strategy employed, the keys to success have included; managing stakeholder expectations, involving the commercial plant design engineers in the planning stage, anticipating subsequent data and sample requirements and most importantly, constructing and operating complex demonstration plants only as a last resort. This paper provides examples of various process development approaches used by Xstrata Nickel and discusses the rationale specific to each project.

Jan 1, 2011

By David G. Winter

The Olive 8 excavation site in Seattle was surrounded on three sides by conditions requiring innovation, careful modeling, and extensive instrumentation to support use of a first-of-its-kind shoring system. The solution combined heavy soldier piles, long and steeply angled tieback anchors, and tightly spaced soil nails to support surcharge loads from a 33-story adjacent tower separated by a narrow alley housing critical utility lines. Land restrictions on two other sides of the site also required innovative applications of traditional methods. The Olive 8 project has won three state and local awards for innovation and has been reported on in Engineering News-Record and has been the subject of two feature articles in the Seattle Daily Journal of Commerce. This paper presents the conditions and site challenges, reviews the design analysis, discusses the shoring performance, and looks at other potential applications.

Jan 1, 2009

All development proposals have to run the gauntlet of the approvals process. Major resource projects are generally subject to particularly intense scrutiny. The key element in the approvals process is that it is about making decisions that take into account the benefits or otherwise to society as a whole - the interests of any one group do not take precedence. Most groups tend to see their relatively narrow interests as representing those of the broader society. Each group develops their arguments for or against a project in isolation, and then presents these to an arbiter in an adversarial situation. From this mire of argument and counter-argument it is often difficult to discern just what the real benefits of a project are, and opportunities for agreement and constructive modification of proposals to meet real concerns are often missed. The contention made in this paper is that the inevitable differences between these various viewpoints should be harnessed to help the proponent to come up with a proposal that is clearly of overall benefit to society and which gains approval. It is better to accept that no one group has a monopoly on wisdom in this area and to engender an environment of creative tension in which the pros and cons can be broadly considered and good planning and design used to produce a proposal that has a high chance of success. There are a variety of ways in which this approach can be implemented. Some of these options will be discussed in terms of their likely applicability to energy projects and their potential for success.

Jan 1, 1992

By Miguel Villegas Vergara

El presente trabajo señala el proceso de desarrollo de la minera Pachapaqui durante el período 1981-1986, la cual se dedica a la explotación y beneficio de minerales polimetálicos. Entre sus objetivos principales está el incremento de la producción, la reducción del costo en la producción y el generar bienestar a sus trabajadores. Los medios para lograr sus objetivos se basan en las reservas del mineral del yacimiento minero, la administración, producción y liquidez del yacimiento. Asimismo, el proceso de crecimiento de dicha compañía conlleva las pautas de planificación, desarrollo minero, metalurgia, el sistema de trabajo (equipo y mantenimiento) y comercialización.

Nov 24, 1986

By Fanny Herrera, David Reaño, Luis Chahua, Elio Murrugara

El crecimiento del depósito de desmonte Pampa Verde es altamente dependiente de las siguientes restricciones: (1) opciones limitadas para extender lateralmente los contrafuertes existentes; (2) la necesidad de satisfacer tanto la estabilidad estática como la sísmica; (3) la necesidad de seleccionar adecuadamente materiales de alta resistencia para el refuerzo; (4) la importancia de realizar pruebas específicas del material geosintético de refuerzo para caracterizar su interacción con el suelo; y (5) la compleja geometría del sistema en conjunto, particularmente para su estabilidad global. El dique de contención existente fue estabilizado mediante su reforzamiento con geosintéticos, el cual consistió en un relleno de suelo compactado con una talud de 2,1H:1V sobre un muro de suelo estabilizado mecánicamente (MSE o suelo reforzado). La estructura MSE involucra dos muros (superior e inferior) con una banqueta horizontal entre ambos. El muro superior está reforzado con geomallas, mientras que el muro inferior consiste en un sistema Terramesh de gaviones reforzados con geomallas. El enfoque general del diseño consideró el diseño de un talud de suelo reforzado con geosintéticos (TSR) que usaría geomallas de alta capacidad de tracción. Las guías de diseño para el TSR propuesto son las emitidas por la Administración Federal de Carreteras de EE. UU. (FHWA-NHI-10-024). Un aspecto clave a considerar en el diseño propuesto fue la adecuada evaluación de la interfase del suelo contra la geomallama, por lo que se consideró un total de cinco productos de geomalla para su posible uso en la construcción del talud de suelo reforzado con geosintéticos.

Sep 20, 2019

By M. K. Larson, R. G. Wade

Researchers at the National Institute for Occupational Safety and Health (NIOSH) are studying the time-dependent response of rock stressed along weakness planes. The objective is to improve mine safety by reducing the number of roof falls that cause injuries and fatalities to miners. Researchers conducted direct-shear tests on mud-stoneovercored from a coal mine roof. Results showed frictional strength weakens with displacement along the shearing planes. Results of direct-shear creep tests also showed time-dependent deformation. Test measurements were compared to classical analytical models. Results suggest that risk of roof collapse may be decreased through layout and support design to reduce creep rates and thus slow progression toward failure.

Jan 1, 2000

By Albert Smith

THE creep properties of metals have as-sumed increasing importance in recent years and many investigations have been made on various phases of the problem. In the past year the annual lectures of the Insti-tute of Metals Division1 and the Iron and Steel Division2 were concerned with this subject, and are excellent reviews. For many years the creep properties of lead and lead alloys have been investigated at the Central Research Laboratories of the American Smelting and Refining Co., and it is hoped that the present paper will contribute knowledge of some of the factors that influ-ence creep. Lead, being a metal that recrys-tallizes readily at room temperature, is an excellent material upon which to investi-gate creep phenomena because of the sim-plicity of the apparatus needed, and it might be expected that results would apply to some extent to elevated-temperature tests of other metals.

Jan 1, 1940

By Richard Miller

RECENT studies of creep have made it apparent that plastic deforma-tion may occur in metals under stresses less than the elastic limit as deter-mined from short-time tests. In summarizing conclusions drawn from creep tests by various investigators, Tapsell1 said: "It is evident that if a material has a true elastic range, the elastic limit must represent the maximum stress for no creep." The presence of a. definite elastic limit, represented in single crystals by a critical or threshold shearing stress, is claimed by Schmid2, Elam3 and others who have investigated the plastic deformation of single crystals. However, this "law of critical shearing stress" was deter-mined2 from short-time tests, and the measurement of the deformation was made with apparatus primarily designed to observe large amounts of plastic deformation, not to detect elastic changes. Experimental data recently obtained with highly sensitive instru-ments by A. W. Hanson4 on zinc and by Podaschowsky5 on rock salt indicate that the elastic range in single crystals is considerably narrower than formerly was supposed. Moreover, a theoretical possibility of permanent deformation, under the influence of even the smallest shear stress in single crystals above a certain temperature (Td), has been developed by G. I. Taylor6. This evidence seemed to warrant an examination of the elastic limit in large single crystals by means of creep tests. The first metal chosen for examination was zinc.

Jan 1, 1936