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By John Drew Ridge

Tables showing world trade in metallic mineral raw materials during the years 1953 through 1957 have been prepared for the following twenty-one commodities: alumina, aluminum, bauxite, chromite, copper concentrates, partly refined and fully refined copper metal, iron ore, pig iron, iron and steel (simple shapes), lead concentrates, lead metal, manganese ore, mercury metal, nickel ore, concentrates, and matte, nickel metal, raw pyrites, sintered pyrites, tin concentrates, tin metal, zinc concentrates, and zinc metal. In each instance, the amounts given by the importing country were used except when statistics from the importing nation were lacking, incomplete, or misleading. To show the considerable divergence between importing and exporting country totals for the same years, the complete mercury table is given and, in parallel columns, shows the comparable tonnages of importers and exporters. Tables for the other twenty commodities are presented in summary form. The data of the concentrate tables are used with those of the corresponding metals as a basis for a discussion of trade in concentrates versus trade in metals. The data of all twenty-one tables provide the basis for testing the thirteen rules governing international trade in metal raw materials which I first published in Mining Engineering for July 1955. Because the 1953 through 1957 data are far more complete and considerably more extensive than those on which the 1955 rules were based, it was found possible to deduce five additional rules and to modify three of the original thirteen appreciably. The full text of the eighteen rules is given.

Jan 1, 1960

By Neall. George M.

No method of roof control yet devised has proven to be universally acceptable for the wide range of strata conditions experienced in U.S. coal mines. However, a relatively new innovation, the roof truss, has proven itself capable of preventing roof failures which both conventional and resin bolting could not. Presently, the economics of roof trusses are not favorable when compared to bolting due primarily to drilling and installation procedures, but this is expected to change with improved truss and equipment designs. To realize the full potential of this new method of roof control, design criteria are needed which can optimize the effect of the truss for varying strata conditions. A review of the literature reveals that some work has been conducted on the roof truss. 1 Gambrell and Haynes (1970) showed that the roof truss is superior to angled roofbolts installed through a header. Sheorey, Verma, and singh2 (1973) used statics to prove that the optimum angle of inclination should be greater than 450? However, to date, no systematic attempt has been made to establish design criteria. In this report, the problem was approached in three ways. First, model studies were performed to determine general trends of truss support as a function of a number of variables. This provided a better understanding of the support mechanism involved. Secondly, beam theory was employed to calculate the actual support capacity of a truss, realizing the many simplifications, assumptions, and shortcomings of this approach to such a complicated problem. Last, field testing will be utilized to test the hypotheses previously developed and provide hard data to further synthesize roof truss design criteria. Field testing has recently commenced and should be complete before mid 1977.

Jan 1, 1977

By T. W. Martin

The use of conveyors in large, open pit mines and their drawbacks are discussed. Technological developments such as long distance conveyors capable of handling large rocks are explored. The development and testing by the Bureau of Mines of a prototype crib and cable conveyor for handling large rocks are discussed, and possible modifications of the concept for a production model are examined.

Jan 1, 1984

By Victoria Vaccarezza, Corby Anderson

The demand for rare earth elements for everyday technology and applications has initiated much research into the extraction and recovery of these rare earth elements. An otherwise unknown group of minerals, eudialyte is a zircon silicate consisting of rare earth oxides (REO), contained in a unique mineral structure and represented by a complex chemical formula. Research into extraction and recovery of rare earth elements involves various beneficiation and hydrometallurgical techniques. The goal of beneficiation being to efficiently liberate and upgrade the REO content, followed by hydrometallurgy to extract the desired elements. This overview will discuss previous research on treating eudialyte group minerals via different mineral processing and extraction techniques.

By Warren C. Gerler

An overland belt conveyor system is installed for only one reason to save money. It must pay its way on a ton-mile basis over a stated period of time, and do so in competition with other forms of transportation. Such a system with its economies has recently been installed at Simco-Peabody's mine near Coshocton, Ohio by Link-Belt Company. Three miles in length, this system carries coal from open pit and underground mining facilities to the Conesville Power Plant of Columbus & Southern Ohio Electric Company. The coal was formerly trucked from the mine direct to the power plant; but over the years the mining operations have moved progressively farther and farther from the plant, making the over-the-road hauling distance correspondingly greater. Simco-Peabody has mining operations over a considerable area just east of the Conesville Station. The majority of the coal is recovered by conventional strip mining. Some underground mining` is performed by the high wall method.

Jan 1, 1963

This one day field trip is sponsored by the Denver Region Exploration Geologists? Society, May 14th 2009. The trip highlights major geologic features and some notable uranium occurrences along the north-south mountain-basin boundary southwest of Denver and continuing north to Fort Collins, Colorado. Uranium deposits visited include sandstone?hosted roll front type and polymetallic veins hosted in metamorphic rocks. A replacement ?episyenite? type occurrence is considered via description and hand samples but is not visited owing to logistical constraints. Recovery methods addressed include underground mining and in-situ leach recovery. Samples of Precambrian basement rocks, deposit host rocks, uranium ore samples, and ore polished sections viewed by reflected light microscopy will be available. A road map showing the locations of the stops serves as the front cover of this field guide. The Robinson episyenite-hosted occurrence (not visited) is labeled as Stop 6. A stratigraphic column is provided which shows the position of the host rocks at each stop (Figure 1-1).

Jan 1, 2009

By Keros Cartwright

Sanitary landfilling has become one of the most widely used methods of disposing of solid refuse. A principal concern of regulatory agencies and the public itself is that landfill operations do not degrade the physical environment, including water resources, and the ground-water reservoir in particular. Ground-water and engineering geology can guide landfill operations into suitable terranes or develop measures to compensate for any natural limitations at a particular site Experience and research in Illinois suggest four activities relating to landfill disposal that warrant attention by geologists and engineers: (1) Regional delineation of favorable and unfavorable hydrogeologic conditions to facilitate planning and preliminary screening of potential landfill sites. (2) Site evaluations, with considerations of geologic materials, topography, water levels, flow systems, and local occurrence and use of water resources. (3) Re- search on aspects of the hydrogeologic environment that control effects of, or are modified by, landfills. (4) Formulation of practices in the siting, construction, and operation of landfills that prevent, mitigate, or isolate deleterious effects. The first two activities are basically in the domain of earth science, requiring the application of fundamental concepts of geology and hydrology and conventional site-exploration methods. The third activity, research, requires contributions from geology as well as other disciplines, including soil physics, sanitary engineering, and chemistry. The fourth calls for policy decisions by regulatory agencies and elected officials, using the contributions of scientists and engineers.

Jan 1, 1970

By Samuel Rigert, Marco Bettelini

"INTRODUCTION AND OBJECTIVES Long rail tunnels require in most cases powerful mechanical ventilations. Besides requirements related to normal operation and maintenance, operational safety always requires a high level of smoke management. Identifying the optimum ventilation concept is essential for achieving proper performance and safety while keeping investment and operational cost at a reasonable level. For the purpose of the present paper, long tunnels have a length of typically 20 km or more. This is related to the European classification of trains (TSI 1303/2014), where the maximum distance from the portals to a firefighting point and between firefighting points is limited to 20 km (only category B passenger rolling stock allowed) or 5 km (general case). From TSI 1303/2014 it can be concluded, that tunnels over 20 km require in any case emergency stations with complex mechanical ventilations. Based on the experience arising from a number of recent projects in the European area, including in particular Gotthard (GBT), Lötschberg, Lyon-Tourin (LTF), Brenner (BBT) and Gibraltar, safety-relevant issues related to the ventilation of long railways tunnels are reviewed in this paper. Amberg Engineering is directly involved in these challenging design tasks and can provide first-hand experience and know-how. As a particular highlight, special attention is devoted to the longest tunnel worldwide, the 57 km long Gotthard Base Tunnel, which will be commissioned in 2016. THE GOTTHARD BASE TUNNEL Overview The Gotthard Base Tunnel will be commissioned in 2016 (official inauguration on the 1st of June and beginning of regular operation on the 11th of December) and will be the worldwide longest tunnel. Its complex and powerful ventilation system is very representative for many other long tunnels and is used as reference in this paper. Therefore, a few key characteristics of the Gotthard Base Tunnel and its ventilation system will be described in some detail in this initial chapter. The Gotthard Base Tunnel (GBT) consists of two single-track tunnel tubes with connecting galleries every 312 meters. Two so-called multi-functional stations (MFS), located at roughly 1/3 and 2/3 of the tunnel length, host the key equipment for normal and for emergency operation. At these locations, double crossovers allow trains to switch from one tunnel tube to the other. An emergency station is located in each multifunctional station, allowing trains to stop in case of emergency. The general layout of the GBT is presented in Figure 1."

Jan 1, 2016

By Ed Sullivan

"Australia is one of the richest continents when it comes to mineral extraction, ranging from exotic projects like the Olympic Dam — a copper, silver and uranium mine believed to have the world’s largest uranium resource — to the extensive iron ore, nickel, coal and gemstone formations that provide many of the country’s most rewarding exports.Among the challenges to succeed in this industry is the ability to provide efficient “pitto- port” infrastructure performance, which essentially means ensuring that minerals move seamlessly from the point of extraction to the facilities that can then move them to international market destinations.To provide such efficiencies, avoid human error and facilitate automated mining functions, producers are increasingly turning to fiber optic cable suppliers for “end-to-end” communications and control solutions. Many such solutions include ruggedized cable and connectors that ensure the survival of fiber-based DCS/PLC automation/ control architectures for various types of mining operations, even in the harshest environments.Integrating the solutionAs industrial Ethernet and fiber optic cable emerges as the medium of choice in many industrial arenas, communication and control integration using the most appropriate products for a specific application is increasingly important.“This whole ‘pit-to-port’ performance concept is focused on control and process automation,” says Boyd McDonald, Founder and Managing Director at Datalek Systems & Electrical, Rockhampton Area, Australia. “It also means bringing reliability to networks and providing the needed bandwidth. An appropriate plug-and-play solution is also important because it takes human error out of the equation.”Datalek Systems & Electrical, is responsible for the design, installation and maintenance of numerous fiber optic communications systems including those that involve automation, security, access control an CCTV systems for open-pit and underground mining operations as well as LNG and coal seam gas facilities."

Jan 1, 2015

By Joel L. Morrison

The preparation of coal-water slurry fuel (CWSF) has the potential to be a commercially viable technology for the coal industry. The technology base required to prepare stable CWSF using grinding circuits has been developed over the past decade and is now being applied to the preparation of CWSF from wet coal fines which are generated during coal beneficiation. When preparing CWSF, the optimum CWSF formulation must be determined to ensure that the fuel will be stable while having acceptable atomization and combustion properties, and the production run must be monitored closely to ensure that the CWSF quality is maintained. This paper describes the CWSF formulation process, CWSF preparation circuits, and some of typical problems encountered in, and solutions to, the transportation and storage of CWSF.

Jan 1, 1993

By G. A. Rosario, G. Peach

Twin 8.5 m diameter, 10 km long headrace tunnels under overburdens of up to 1870 m were excavated for the neelum jhelum hydroelectric project in north-eastern pakistan using two main beam gripper tunnel boring machines (tbms). Rock bursts were encountered and presented a significant danger to personnel and equipment. Micro seismic monitoring was installed to analyze rock burst characteristics and to create a database for future reference. Correlation of rock burst characteristics improved the ability to predict the likelihood, location, severity, and number of rock burst events. This paper presents the analysis of the micro seismic data

Dec 1, 2022

By Jr. Zink

An economic and operational evaluation of the unrecovered metal, physical conditions, and chemical environment in a leach pad should be made prior to decommissioning. This evaluation will help determine the possibility and method of secondary and/or enhanced metal recovery and the method(s) to be used for detoxification and heap closure. The evaluation requires quantitative sample collection in a locally variable, yet grossly homogenous material. An assessment of a valley fill heap leach pad was made using a technique borrowed from placer technology called sonic drilling. The sonic drilling technique produced very satisfactory core recovery and sample quality. At this site, drilling results demonstrated that the method of heap construction produced expected features after extensive long term leaching. Rather than a uniformly homogenous pile of metallurgically depleted crushed ore, an assemblage of solution channels, un-oxidized sections, unleached areas, and compaction due to various factors, were found. These conditions are thought to represent a normal, rather than unique, situation for a valley fill heap leach. The lack of this information can have a significant impact on the economics and methods of heap re-handling and ultimate closure.

Jan 1, 1992

By T. Chandler, R. Buchan, J. H. Blowes, E. G. Haldeman

The regional geological setting and nature of the serpentinized ultramafic rocks are described. It is postulated that lateritization started in Miocene time. Repeated uplifts led to at least four physiographic cycles and to the development of a mature lateritic soil profile. Complete profiles are subdivided from top to bottom as follows: Zone A - chocolate-brown limonite; Zone B - ochre-brown limonite; Zone C - soft serpentine; Zone D - hard serpentine; Zone E - serpentinized peridotite; Zone F - ultramafic rock. Zones A and F rarely attain ore grade. Canga is conspicuously absent. Rocky ore of Zones D and E amounts to 40%, limonite ore of Zone B to 25% of total ore reserves. Nickeliferous serpentine is the major crystalline phase in Zone C. In this zone and deeper, crystalline quartz occurs, particularly in fracture zones where nickeliferous cryptocrystalline quartz is of ten accompanied by garnierite.

Jan 1, 1979

By M. K. Mohanty

A modified coal flotation characterization procedure, referred to as the Advanced Flotation Washability (AFW) technique, has been developed which, compared to traditional procedures, provides a more accurate prediction of the optimum separation performance achievable by a froth flotation process. The AFW procedure uses a vertically-baffled flotation column which provides enhanced selectivity among particles of varying degrees of hydrophobicity due to a plug-flow environment and an improved carrying-capacity environment. In fact, the separation performance of the traditional procedures was enhanced by increasing the possibility of operating under improved selectivity conditions. The separation performance provided by the AFW procedure was superior to that obtained from multiple cleaning stages using commercially-available flotation columns under both kinetic and carrying-capacity limiting conditions.

Jan 1, 1997

By R. Owen

An overwhelming amount of data can be collected around the blasting process. This information can include blasting product, pattern design, blast results, and routing. It is only when these data sources are combined in a concise and accurate form that they are of real use in determining the safety and economic implications of each parameter. Two key technological aspects of blasting are drill fleet management (DFM) and size fraction analysis (SFA). As these technologies are integrated as near-real-time measurement and QA/QC tools, the resolution and realization of blasting parameters is significantly increased. The Freeport-McMoRan Morenci Mine has integrated these technologies along with other existing database structures to create a responsive and sustainable tool for reconciliation, forecasting and parameter matching. This ability allows Morenci to customize blast patterns to meet the criteria most critical to each shot, whether the impact is influenced by routing and recovery, equipment maintenance or safety concerns. DRILL FLEET MANAGEMENT The current DFM was stabilized in its current form in mid 2009 after database and hardware maintenance met stability requirements. Currently the system is running on 12 production drills. The system receives pattern layout and is capable of semi-autonomous drilling over the entire district. The fleet is capable of drilling in highly altered intrusive units and hard granites through the range of sedimentary and volcanic units that comprise the Morenci District. The system brings a level of accuracy not achievable with earlier paint-marked patterns. Depth control is also increased along with more consistent wear and maintenance patterns due to semi-autonomous drilling.

Jan 1, 2011

Extensive testing in the past ten years has shown that where a uniform natural gamma background is present in the strata bordering the seam, the thickness of the boundary coal left in place after mining can be determined by measuring the attenuation of that radiation (Nelson and Bessinger, 1989). Measurements made by the authors in underground mines in Pennsylvania, West Virginia, Ohio, Illinois, and Kentucky, and by others in Wyoming and New Mexico, have shown the presence of such a gamma background (Nelson, 1989). Natural gamma coal thickness sensors of several configurations have been tested in mines owned and operated by the Consolidation Coal Company in Pennsylvania and west Virginia (Nelson and Bessinger, 1988).

Jan 1, 1990

By John Newby, Ulf Gwildis, Ken Massé, Guillaume Roux

How to connect an effluent conveyance tunnel to riser shaft and diffuser arms of an outfall system is dictated by the ground conditions, which ideally include rock or soil strata of low permeability. Where such favorable conditions are beyond reach, both the complexity of designing and the risk of constructing this crucial system connection increase disproportionally. This paper describes the considerations that went into the approach of connecting a 5-m-diameter TBM drive with the in-river riser shaft of the Annacis Island WWTP New Outfall System in the highly permeable Fraser River sands at hydrostatic pressures exceeding 3 bar.

Jun 23, 2024

By M. Raffaldi, J. Johnson, M. Stepan, D. Benton

"The Office of Mine Safety and Health Research (OMSHR), Spokane Mining Research Division (SMRD), is continuing its High-Energy High-Displacement (HEHD) testing of field-scale shotcrete panels. A test program was developed to determine the relationship between applied force, displacement, and energy for both unreinforced and reinforced shotcrete panels. Reinforcement options consisted of synthetic macro-fibers, sprayed polyurea liners, chain-link fence, welded-wire mesh, and combinations of these products. During testing, photogrammetry was used to measure the geometric changes of the panels, including volume changes and panel cracking. These measurements were correlated with the load and displacement data, allowing visual observation to be related to the applied force and displacement. The test results provide a comparison of the mechanical performance of the various panel types and can be used by the practicing engineer to evaluate installed support based on visual observation of cracking and deformation. Visual assessment of the loading cycle and strength capacity of shotcrete in underground excavations will improve mine safety by providing a means to quantify the stability of installed shotcrete support. INTRODUCTION The National Institute for Occupational Safety and Health (NIOSH), Office of Mine Safety and Health Research (OMSHR), Spokane Mining Research Division (SMRD) is continuing research on the behavior of shotcrete when used as the surface support component in mining ground support systems. Ground control safety often depends on supporting, or at least containing, the ground between the rockbolts. Shotcrete and mesh, in various combinations and with other components, are often used to accomplish this (see Figure 1). Maintaining support pressure during ground deformation is key to the performance of these systems, and to ensuring miner safety. However, the toughness of a ground support system–the ability to maintain strength over large deformations–is difficult to quantify. Researchers at SMRD have responded to this deficiency by designing a full-scale test device, described previously by Martin et al. [2015a], and beginning a testing program to assess the behavior of shotcrete surface support reinforced with a variety of products including: fibers, chain-link mesh, welded-wire mesh, spray-on polyurea liners, and combinations of these products. This paper presents the findings of these tests."

Jan 1, 2016

By R. S. Jurani

Sunshine Mining Company's Kellogg operation is the primary silver producer in the United States, and maintaining a comfortable working environment in this deep underground mine historically has been a complex and costly problem. To improve the ventilation and cooling systems at a time of declining and uncertain silver market, it was proposed to optimize the performance of existing facilities at minimum cost. This paper discusses a 2-year, $400 000 optimization program that resulted in increased total mine airflow, cooler ambient temperatures, reduced compressed air usage, and lower energy consumption by primary fans, air compressors, and refrigeration plants, thereby saving the company approximately $650 000 per year.

Jan 1, 1987

By M. Raffaldi, J. Johnson, M. Stepan, D. Benton

"The Office of Mine Safety and Health Research (OMSHR), Spokane Mining Research Division (SMRD), is continuing its High-Energy High-Displacement (HEHD) testing of field-scale shotcrete panels. A test program was developed to determine the relationship between applied force, displacement, and energy for both unreinforced and reinforced shotcrete panels. Reinforcement options consisted of synthetic macro-fibers, sprayed polyurea liners, chain-link fence, welded-wire mesh, and combinations of these products. During testing, photogrammetry was used to measure the geometric changes of the panels, including volume changes and panel cracking. These measurements were correlated with the load and displacement data, allowing visual observation to be related to the applied force and displacement. The test results provide a comparison of the mechanical performance of the various panel types and can be used by the practicing engineer to evaluate installed support based on visual observation of cracking and deformation. Visual assessment of the loading cycle and strength capacity of shotcrete in underground excavations will improve mine safety by providing a means to quantify the stability of installed shotcrete support. INTRODUCTION The National Institute for Occupational Safety and Health (NIOSH), Office of Mine Safety and Health Research (OMSHR), Spokane Mining Research Division (SMRD) is continuing research on the behavior of shotcrete when used as the surface support component in mining ground support systems. Ground control safety often depends on supporting, or at least containing, the ground between the rockbolts. Shotcrete and mesh, in various combinations and with other components, are often used to accomplish this (Figure 1). Maintaining support pressure during ground deformation is key to the performance of these systems, and to ensuring miner safety. However, the toughness of a ground support system–the ability to maintain strength over large deformations–is difficult to quantify. Researchers at SMRD have responded to this deficiency by designing a full-scale test device, described previously by Martin et al. [2015a], and beginning a testing program to assess the behavior of shotcrete surface support reinforced with a variety of products including: fibers, chain-link mesh, welded-wire mesh, spray-on polyurea liners, and combinations of these products. This paper presents the findings of these tests."

Jan 1, 2016