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By T. MacKinnon, M. C. Bétournay, D. Eastick, F. C. Delabbio, C. Graves

"The successful implementation of a new technology in an underground production mine requires many challenges to be overcome. These challenges include mine hardening of new technology, mitigation of safety risks and hazards, mine operation support, and technology transfer to mine staff. In the end, the majority of these challenges relate to the human aspects of implementation. The approach selected to overcome these challenges must be customized and appropriate for each unique situation.This paper outlines the approach used to address these challenges as part of successful implementation and resulting demonstration of the hydrogen fuel cell locomotive at the Placer Dome (CLA) Limited Campbell Mine. This technology demonstration at Campbell Mine is critical for determining technical, regulatory, and implementation aspects to be incorporated into future fuel cell prototypes such as the LHD project."

Jan 1, 2005

By S. Aram

Product Lifecycle Management (PLM) solutions have been serving as the basis for collaborative product definition, manufacturing, and service management in many industries. They capture and provide access to product and process information and preserve integrity of information throughout the lifecycle of a product. Efficient growth in the role of Building Information Modeling (BIM) can benefit vastly from unifying solutions to acquire, manage and make use of information and processes from various project and enterprise level systems, selectively adapting functionality from PLM systems. However, there are important differences between PLM?s target industries and the Architecture, Engineering, and Construction (AEC) industry characteristics that require modification and tailoring of some aspects of current PLM technology. In this study we examine the fundamental PLM functionalities that create synergy with the BIM-enabled AEC industry. We propose a conceptual model for the information flow and integration between BIM and PLM systems. Finally, we explore the differences between the AEC industry and traditional scope of service for PLM solutions.

Aug 1, 2013

By John Rudolf

Metropolitan Washington Airport Authority is currently undertaking the first Phase of Metro?s Extension to Northern Virginia. A wide range of tunnel options was considered for the Tysons Corner segment that involves about 20,000 feet of track and four stations. After consideration of many options that involved EPBM single track tunnels, NATM tunnels and large bore tunnel concepts for the entire Tysons alignment, the design now being progressed into construction involves two 520 meter (1,700 feet) long soft ground NATM tunnels with several hundred feet of cut-and-cover construction. The paper discusses the process that led to selection of the short NATM tunnels as the most feasible of the options considered for Tysons.

Jan 1, 2008

Published experimental data on thermodynamic behaviour of cobalt-containing slags have been reviewed and used in validating a recently developed thermodynamic model. The results from the exercise show that the model provides a reasonably good description of behaviour of cobalt in multi-component slag systems. The models for cobalt containing slags, matte and oxide solid solution phases were incorporated into CSIRO?s multi-phase equilibrium (MPE) package, which was used to calculate the equilibrium distribution of cobalt between matte and slag phases under various conditions. The results agreed well with the experimental data. Furthermore, the good agreement between the calculation and the plant data indicates that the operating conditions of industrial smelting and converting processes are close to equilibrium. Two diagrams showing the effects of slag chemistry and SO2and O2partial pressures on the distribution of cobalt between phases were generated for conditions similar to smelting and converting processes. These diagrams provide some useful guidelines for developing new strategies to improve cobalt recovery.

Jan 1, 2004

By J. Desroches, J. Burghardt, B. Lecampion, A. P. Bunger

"We present detailed comparisons between theoretical predictions and experiments for the initiation of radial hydraulic fractures transverse to a wellbore. Most of these experiments provide a measure of the time evolution of pressure, length, opening and flux entering the fracture during the test. We compare all these measurements simultaneously to our theoretical predictions, thoroughly testing hydraulic fracture initiation theory, which is shown to be predictive. These comparisons notably emphasize the difference between the initiation pressure (the wellbore pressure for which the fracture initiates) and the breakdown pressure (a misnomer which simply corresponds to the maximum pressure recorded during the test). INTRODUCTION In this paper, we will compare hydraulic fracturing laboratory experiments performed in different tight materials (PMMA, cement, shale) with the predictions from a numerical solution of the governing equations of hydraulic fracture mechanics (e.g. Geerstma & de Klerk, 1969; Detournay & Peirce, 2014). We focus on transverse radial hydraulic fractures initiating from a radial notch at the wellbore wall (see Figure 1). In particular, we will clarify the difference between the initiation pressure (the wellbore pressure at which the fracture initiates) and the breakdown pressure (a misnomer which simply corresponds to the maximum pressure recorded during a test, usually carried out at constant pump rate). This difference stems from the strong viscous effects at play during wellbore pressurization, fracture initiation and early propagation (i.e. fluid entrance in the newly created fracture). It has been observed on a number of experiments (e.g. Weijers, 1995; Zhao et al., 1996) and has a strong practical application, first because the maximum pressure is the most obvious value to report and second because that maximum value is necessary to specify injection systems."

Jan 1, 2015

By HENRY M. PARKS

THE total production of all metals in Oregon to date is estimated at $160,000,000; ~115,000,000 from eastern Oregon and $45,000,000 from the western part of the state. In 1916 the metal production of the state was approximately $4,000,000, while the present annual production has dwindled to a little less than $1,000,000. Western Oregon The state of Oregon contains several metal-bearing areas, widely scattered in different regions. More than half of its coast is fringed with a belt of auriferous sands which sometimes are rich in fine gold. A second mining field, the chief producing one of western Oregon, is situated in the southwestern part of the, state and includes Jackson, Josephine, Douglas, Coos and Curry counties. It may be considered as the northern extension of the gold and copper belt of California. A third region in western Oregon is that on the western slope of the great Cascade range in the Bohemia, Blue River, Quartzville, North Santiam and Ogle Creek districts-from the Siskiyous on the south almost to the base of Mt. Hood near the Columbia River on the north.

Jan 1, 1925

South Africa has joined the league of other major Western World countries by officially adopting its own code for public reporting of Mineral Resources and Mineral Reserves. The recently published South African Code for Reporting of Mineral Resources and Mineral Reserves (SAMREC Code or Code) (SAIMM 2000) is presented here in its local and global context. The main aspects of the Code are listed and elaborated upon. The Code has been written with the participation of the major South African stakeholders in the field including Government institutions, the legal confraternity and the mining industry. Relevant foreign organisations, such as the Australasian Joint Ore Reserves Committee (JORC) and the United Nations contributed to its compilation, and supported it. The Code thus enjoys endorsement both locally and, to a large extent, overseas. The Code is modelled on, and is 90 per cent compliant with, the Australasian Code for Reporting of Mineral Resources and Ore Reserves (JORC Code) (AusIMM, 1999). The paper also elaborates on the duties and responsibilities of Competent Persons signing off resource and reserve reports and on the new listing requirements of the Johannesburg Securities Exchange (JSE), formerly the Johannesburg Stock Exchange, which has officially adopted the Code.

Jan 1, 2002

By Brad Bulow

Blasting is an essentially violent process aimed to disrupt and loosen rock for productive excavation. Some dilution of any ore present is the inevitable result. This makes blasting a dirty word to most geologists, particularly in narrow vein gold mines. A 1% increase in gold recovery may be worth $1 M extra revenue to a large mine.

Jan 1, 2000

By Frank Hirthammer

Productivity, customer relations, and effectiveness of work depend to an ever-increasing extent on a functioning logistics system tailored to the needs of the user. Of course, it is not possible to cover and explain all aspects of the logistical requirements of even a small part of an industry, in a single article. The article speaks specifically about the particularities and differences in the logistical requirements in the explosives sector. Starting with questions of safety, handling and quality up to the legal basis, there are special requirements regarding the logistics in the explosives sector. The results of innovative logistics solutions are presented using three examples from daily work practice.

Jan 1, 2019

By Thierry Bernard, J. M. Laboz

2000 HIGH-TECH SEMINAR Blasting Technology, Instrumentation and Explosives Applications

Jan 1, 2000

By James W. Echerd

Anthracite preparation developments, particularly in the early days of the anthracite industry, formed the basis for the modern coal preparation plants that have become so essential to the coal industry today. The anthracite industry, from early in the 19th century until relatively recently, was a leader in mining, preparation and marketing of coal, and played a leading role in the development of the industrial America we know today. Anthracite was discovered in America in about 1760--the story of Necho Allen is well known--but the rediscoveries leading to mining operations took place about 50 years later. The Wurtz brothers in 1815 at Scranton, the Smith brothers at Wilkes-Barre in 1807, Beach in Hazleton in about 1814, and Boyd in 1816 at Shamokin were all instrumental in promoting early mining and marketing of anthracite (J3. The early canals and railroads were built for the specific purpose of moving anthracite to the market areas. Eventually, the industry grew until, in 1917, it reached a production zenith of a little over 100,000,000 tons, representing about 20 percent of the total coal output in the United States. Almost half of the anthracite produced that year was consumed for domestic heating, a utilization that had dominated the industry for almost 100 years. Initially, anthracite had to be used by gunsmiths and blacksmiths, after which had followed the consumption of extensive quantities for railroads, blast furnaces and foundries, and electric power generation. Most of the markets have been lost to coke, oil, and natural gas. Near the anthracite regions, however, significant quantities are still used for domestic heating, power generation, carbon black manufacture, blending with bituminous coal to make metallurgical coke and fuel, and for other industrial purposes. Thus, anthracite production has not been entirely committed to history, but remains an active industry that follows modern practices in the mining, preparation, shipping, and utilization of a fuel that is still a valuable adjunct to the national economy. In fact, its inherent low sulfur content may make it an important fuel of the future. Estimates indicate there are reserves of anthracite to last for 300 years at a consumption rate of 50,000,000 tons/year. Anthracite Preparation Yesterday A 170-year history of the anthracite industry obviously is not the purpose of this discussion. A complete history of anthracite preparation, the rather unglamorous step in the processing of "mine run" hard coal to make it suitable for the user, is also not practical. Hence, the purpose of this report is to trace the development of some of the most important processes used through the years to meet a part of the demand for energy developed by our modern society. Anthracite preparation in the early days of the industry consisted solely of separating slate from the coal, by hand, underground (Z). This method prevailed for almost 20 years until wrought iron hand rakes were introduced to separate the large and small sizes. Shortly thereafter, the first attempts were made to size and clean the coal aboveground. The coal was dumped on a perforated cast iron plate, and men used sledge hammers to break the larger pieces into smaller sizes suitable for the market. The smallest sizes--that is, the material that went through the plate--were thrown away because they had no value at that time--a concept that existed for many years and actually was the basis for the subsequent "river" coal production and the many silt banks which are landmarks in the anthracite region. The larger sizes, at that time, sold for 50 cents per ton. The Batten breaker, or roll crusher, was invented in 1844, followed soon thereafter by the Snell-Diehm breaker (A). The latter had disadvantages, including excessive waste and fixed product size, but it later was improved in these respects. A breaker was also developed at Minersville, Pa., at about the same time that processed 200 tons of coal per day, using roll crushers and circular screens (1). Handpicking, from the beginning of anthracite preparation, was an important part of the cleaning process and was still being practiced as late as 1950. It was this process that involved the "breaker" boys of coal region lore. How much good handpicking accomplished depended on how much impurity was present in the coal--the more the impurities, the greater the reduction in ash. Thus, high-impurity streams were significantly improved, whereas picking of relatively clean coal was mainly to show an effort to make a quality product. As indicated, picking is largely a visual operation. It was and is wasteful of coal in the larger sizes since some good coal is always associated with the bad. However, it was probably much more effective' in the larger than the smaller sizes.

Jan 1, 1971

By J. C. White

"This paper was prepared for and presented at a lecture series on ""Materials Randling"" at McGill University. The development of trackless mining at Gaspe Copper Mines, Limited is described, showing the changes in mining method and the part played by the mobile equipment in the evolution of this highly mechanized underground operation. Comparisons of loading and hauling machines are given and an attempt is made to predict some possible future developments.INTRODUCTIONTHE PROPERTY OF GASPE COPPER MINES LIMITED is located in the Gaspe Peninsula of the Province of Quebec, 60 miles west of the village of Gaspe and 25 miles south of the St. Lawrence River. The original discovery of low-grade ore was made at Copper Mountain in 1921. Subsequent exploration revealed the richer Needle Mountain orebodies, and eventually in 1951 the decision was made by Noranda Mines to build the mining, concentrating and smelting complex (Figure 1). Construction and development of the mine was commenced in 1952 and production started in 1955."

Jan 1, 1968

By Matteo Montesi

Deep foundation elements are often used as discrete elements in externally supported earth retaining structures such as soldier piles and lagging walls, secant/tangent pile walls, anchored walls, etc. These structures can be designed using different approaches such as conventional limit equilibrium methods, finite element/difference analyses, and soil spring (p-y) analyses which are contained in various commercially available computer programs used by engineers worldwide. Although these programs usually undergo various degree of verification and validation, users must be aware of each program’s limitations and conditions in which each design approach should or should not be used. These programs may incur difficulties when non-continuous deep foundation elements are used as part of the retaining system and in cases of non-uniform geometry where closed-form solutions are not available. Design input parameters such as passive arching width, wall-to-soil friction, and p-multipliers (pm) are not always given enough attention which may result in potential design deficiencies. This paper presents the main features of various earth retaining structure design approaches and discusses their advantages/disadvantages. The paper addresses some of the limitations and difficulties that may be faced with when utilizing non-continuous discrete deep foundation elements and identifies key elements that are sources of potential deficiencies and errors. An example comparing the design outcomes using different design approaches is presented. INTRODUCTION Earth retaining structures are used to retain soil and create or maintain a difference in ground elevation between grades in front and behind the retaining structure. Deep foundation elements have been used for decades to support earth retaining structures. Earth retaining structures that are supported by deep foundation elements are typically referred to as externally stabilized system (O’Rourke and Jones, 1990). An externally stabilized system uses an external structural element, in contrast to internally stabilized systems which rely on reinforcements installed within and extending beyond the potential failure mass. The design of externally supported retaining structures can be accomplished using different approaches, which can be challenging under certain conditions. Each approach has been discussed extensively in available literature, and is well summarized in the and Federal Highway Administration (FHWA) guidelines. The objective of this paper is to present the most widely used design approaches and discuss their limitations and difficulties in one concise and brief document, giving the reader a good source for comprehensive understanding of the various design approaches, supported by a technical example. This paper is not intended to be a comprehensive review of all available design methods and formulations available in the literature.

Jan 1, 2018

By Yoginder P. Chugh

This paper discusses an ongoing field study in southern Illinois (USA) that focuses on: 1) Identifying mechanisms of instability in the set-up rooms (SR) and their T-junctions with headgate and tailgate entries, 2) Developing alternate 3-entry and 4-entry set-up rooms geometry using 3-D numerical analyses, 3) Implementing developed geometries in cooperation with mining professionals and regulatory agencies, and 4) Demonstrating performance of implemented geometries through field monitoring. Illinois longwall mining operations typically experience ground control problems (roof falls, rib sloughing, floor heave, etc.) within SR layouts and around the T-junctions of SR. These occur around the areas where the SR for adjacent longwall face (to be mined) connect with the SR of the previously mined face, and around the tail-gate entries of the mined-out longwall face and around the T-junctions of SR. The problems manifest as highly fractured immediate roof strata, major shear zones in the roof, horizontal displacements within the excavations that result in shearing off the heads of the bolts, floor heave and severe rib sloughing. Similar observations have also been made in longwall mining in Utah.

Aug 1, 2013

By M. C. Holton

South Africa has the world?s largest in situ deposits of platinum group metals, but economically exploitable resources are shrinking due to escalating costs and technical challenges. The South African National Research and Development Strategy comments that an increase in the knowledge intensity of the resource-based sectors is required to turn these resources to account. Highly trained human resources, continuous improvement, technological innovation, and smart acquisition of know-how will become the major differentiators in the global mining market. Mechanization and, ultimately, automation in mining have the potential to reverse the negative mining trend and resolve safety and other challenges. However, the adoption rate of mechanized mining in platinum (and hard-rock gold) has been slow for various reasons. Changing systems from conventional drill?and-blast to continuous mechanized mining is a big step-change endeavour. The problem of transformation is discussed, and the discipline of systems engineering is examined because of its successful application in aerospace and defence.

Jan 1, 2012

By Yao Zhou

Under the United Nations Convention on the Law of the Sea (UNCLOS), the international seabed area (Area) and its resources are the common heritage of humanity (CHH). Patent rights can be incompatible with the CHH doctrine and its underlying principles because patent holders might charge unjustifiably high prices to license patented technology for exploring and exploiting the Area’s resources (creating a "patent holdup" situation), might choose not to license, or might license exclusively when doing so would contravene CHH principles. However, a reasonable patent licensing regime can contribute to sharing the benefits derived from the Area and promote environmental sustainability. Provisions of the UNCLOS that stipulated compulsory technology and financial transfers were removed in the 1994 Agreement relating to the Implementation of Part XI of the UNCLOS but to promote equity and sustainability I propose a voluntary licensing regime modeled on the concept of reasonable and non-discriminatory patent licensing that has been used in other contexts. The International Seabed Authority or another entity will need to coordinate and promote this licensing regime through governance of intellectual property derived from the Area. This proposed approach can better effectuate the CHH doctrine and its underlying principles.

Sep 1, 2014

By William H. Schiffbauer

One of the safety and health research programs of the former U.S. Bureau of Mines Pittsburgh Research Center was the evaluation of technology that will provide remote-controlled operation of mechanized equipment in underground room-and-pillar mining. The purpose of this effort was to enable workers to be located away from the hazardous and unhealthful coal extraction area (the face). As part of this program, advanced machine navigation and control technologies were developed for underground room-and-pillar and highwall coal mining that can be applied to commercially available mining equipment. These technologies use off-the-shelf components and a flexible control software architecture to minimize the effort required to adapt them to mining equipment. An accurate, reliable navigation system that can provide the mining machine's heading and location is a critical requirement for a remote-controlled mining system. After investigating several different types of navigation sensors, researchers selected the Honeywell Ring Laser Gyro Inertial Navigation System (INS) as showing the most promise. It was installed on a continuous mining machine at our Mining Equipment Test Facility. Extensive testing at an open pit (OP) site was also performed. This report describes the INS as it was employed on the mining machine in the laboratory, in the field, and OP tests, and provides the accuracy and performance results of the OP and highwalltests.

Jan 11, 1997

By Jean M. Richardson, Steven R. Williams

"Geometallurgical mapping is a new team-based approach that documents variability within an orebody and quantifies the impact of geology (host rocks, alteration and structure) and mineralogy on grinding, metallurgical response and metal recovery processes. The quantitative, spatially constrained database that results can be readily integrated into 3-D block models and mine planning activities. Thus it is an important tool to reduce the technical risk associated with new mine developments or expansions.Normally undertaken during pre-feasibility or feasibility planning stages, the first step of geometallurgical mapping is to review the geology, mineralogy and other critical parameters and construct a geometallurgical matrix. This matrix provides an objective base to then guide sampling and/or compositing activity for physical property and metallurgical testing. Depending on the project, an array of testing techniques can be used to characterize the ore and feed data into the geometallurgical model.While the range and number of tests needed is project-dependant, the geometallurgical mapping approach allows the development of empirical models or interdependent relationships, grounded by spatially-constrained real data. Extensive data sets collected using less expensive testing methods can be meaningfully correlated with results from complex specialty tests to yield realistic metallurgical recovery data.With geometallurgical mapping completed, the resulting database can be integrated into an overall 3-D block mine model. This means that metallurgical response can be used to realistically forecast the recoveries of specific blocks, perhaps sampled only by drilling. Mine planning can then incorporate the forecasted metallurgical response and generate future project cash-flows; opening the door to economic optimization of the mine exploitation."

Jan 1, 2004

By Steve Dillingham

Today, a typical blaster is likely to wear many hats, including, but not limited to, supervisor, risk manager, safety coordinator, explosives engineer, communicator, as well as professional decision maker. Simply put, a blaster in the new millennium is an all encompassing blast site manager. As you know, accidents on the blast site can range from blast crew injuries to blasting incidents resulting from vibration, flyrock, misfires, etc. Not surprising, the incidents can quite often be traced back to direct preventable human action on the blast site. They can, however, frequently be avoided, if responsibly identified early and managed properly by an efficient blast site manager. Your company cannot afford to simply employ blasters; good blast site managers are necessary to produce the safest results possible.

Jan 1, 2001

By T. Markus, K. Hilpert

Discharge vessels of advanced light sources are made of translucent polycrystalline Al2O3(PCA).These tubes contain salt mixtures, which essentially consist of metal halides. The salt mixture is present as a melt at the coldest spot of the vessel under operating conditions and vaporizes partly. The temperatures of the coldest spot range between 1200 K and 1300 K, depending on the lamp performance. The maximum wall temperatures range up to 1500 K and for special purposes up to1700 K. Important constituents of the melt are alkali halides AX (A = Na, Cs, X= Br, I) and rare earth metal halides LnX3(Ln = Dy, Ho, Tm). Severe corrosion attack on the wall material is observed in the PCA discharge vessels. The aim of this work is to elucidate the corrosion mechanism. Annealing experiments under well defined temperatures were carried out in order to understand the complex chemical corrosion processes. Two different annealing vessels were used, one for experiments under isothermal conditions with a temperature of 1473 K and one for experiments with a linear temperature gradient from 1450 K to 1600 K. The vessels were filled with salt mixtures of different compositions and annealed for 1000 h. The corrosion attack was characterised by XRD, analytical electron microscopy, high temperature mass spectrometry, and chemical analysis of the salt melts. The results of our investigations show that the corrosion attack is caused by vapour species and by the salt melt. The most severe corrosion is observed in vessels filled with mixtures of alkali halides and rare earth metal halides. No corrosion of the alumina is practically observed if pure alkali halides or pure rare earth metal halides are present in the annealing vessel. Keywords: thermodynamic, corrosion, lamps, metal halide salt

Jan 1, 2004