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By T. Rockley, B. Goertz, S. McDaniel, J. Brune, K. Bakhsh

"Researchers at the Colorado School of Mines, under a project funded by the Alpha Foundation, have developed a working prototype of a dust sample collection device designed to determine if sufficient rock dust has been placed in an underground coal mine to prevent coal dust explosions. When used in conjunction with the Coal Dust Explosibility Meter (CDEM), the device will provide near instantaneous results on the quality of rock dusting at the tested location. The sampling device applies a pulse of air to a testing surface and collect a representative sample of mine dust based on the pneumatic entrainment process during a mine explosion. The use of both physical testing and Computational Fluid Dynamics (CFD) modeling has allowed researchers to refine the design to accurately represent the particle entrainment and optimize the sample size collected for the CDEM. The prototype is being tested in a mine environment to produce information of usability and practical aspects of mine dust sampling. This paper is a progress report summarizing the current status of sampler development. Researchers expect to have a fully developed and tested sampler in early 2016. INTRODUCTION Underground coal mines face the danger of methane and coal dust explosions. The disaster at Upper Big Branch mine (2010) has demonstrated the impact of a violent coal dust explosion that fatally injured 29 miners. Reviewing the history of coal dust explosions, researchers found that that mine operators and mine inspectors do not have a reliable method of collecting dust samples to assure that sufficient amounts of rock dust have been places to inertize the coal dust. This is a problem specifically with small mines that do not have dedicated safety departments to track rock dusting work. The aim of this research is to develop a simple, portable device that can help underground mine examiners collect dust samples from workings and test the explosibility of the sample near instantaneously. Researchers determined that the current brush-and-pan sampling method required by MSHA (MSHA 2013) is flawed in several aspects: Mechanical sampling with a brush exerts forces on the mine dust that may differ significantly from those present during an explosion. Also, U.S Bureau of Mines research (Nagy 1965) has determined that only the top 0.125 inches of the mine dust layer will be entrained in a coal dust explosion. Using a handheld pan and brush, it is difficult to correctly and repeatably sample a layer of this exact thickness. The following will describe the CFD modeling and experimental testing for the development of the prototype sampler. Researchers analyze the accuracy and performance of the prototype during the course of the build process."

Jan 1, 2015

By Bartłomiej Bursa, Paweł Stefanek, Paweł Stefaniak, Sergii Anufriiev, Wioletta Koperska, Maria Stachowiak

The article presents the main functionality of the DSS class system for monitoring and stability assessment of tailings storage facilities. The presented demonstrator was deployed on the example of the Żelazny Most reservoir - the largest active facility of this type in Europe and the second one in the world. Considered a high-risk structure, it demands a system capable of online analysis of big data from various sources using machine learning, 3D modeling, or GIS mapping with the functions of interactive time-spatial analysis. In this paper, we present a complex calculation module with an integrated user interface.

Jun 25, 2023

Adequate ventilation of coal mine working faces is the single most important technique for controlling respirable dust and methane. Choosing the right technique presents some tough questions. Bureau research has shown that to control respirable dust you must contain the dust near the face, keeping rollback (turbulence) to a minimum. For methane the most effective approach has been to use a blowing brattice or tubing and to create turbulence and disperse the face methane, allowing it to pass over the machine and into the return. It is immediately apparent that the two approaches may counteract one another, thus complicating the decision as to which system may be best for a given situation. At present, Bureau research has developed two successful machine-mounted face ventilation systems to meet these different needs and allow deeper cutting. The fan-powered dust scrubber is designed to control dust primarily associated with blowing face ventilation systems. The spray fan controls methane on exhaust-ventilated sections.

Jan 1, 1988

By Marie-Josée Banwell, Cyriac Sebastian, Giacomo Falorni, Sara Del Conte

Interferometric Synthetic Aperture Radar (InSAR) is a satellite-based monitoring technique that complements other in-situ methods for detecting and measuring surface displacement. Recent advances in data processing algorithms, coupled with the use of high-resolution satellite systems, make it possible to now provide high-frequency InSAR monitoring services, with updated results delivered every time a new satellite image is acquired. The advent of large, continuously updated data sets, however, brings new challenges, including the need to rapidly sift through the data to identify only those points showing relevant ground displacement information. This has been achieved by using trend variation analysis tools, that quickly isolate and highlight only areas of anomalous behavior. The paper focuses on project case studies where continuous InSAR monitoring has proven to be key in identifying displacement trend changes near tunnel alignments.

Jun 13, 2021

By Xinchun Li, Youdi Zhang

AI is one of the computing methods, artificial intelligence performs its calculation by simulating the intelligent behavior of human beings. It is regarded as one of the most important scientific achievements in the 20th century, A1 has been developed rapidly in recent years with the development of the computer technique .The application of AI in the mineral industry has also obtained rapid progress sine AI has been used in early 1980's, such as evaluation of resource, underground mining, surface mining and mine safety etc. It has played an important role for increasing mining efficiency, improving mining management and ensuring the safety of the miner. An integrated A1 system has been developed for coalmines environment management in this paper.

Jan 1, 2002

By Claes G. Björk

Over the past decade mined unlined rock cavern storage for crude oil and refined products has become economically more attractive. This trend is likely to continue, primarily due to advances in excavation methods, rising steel costs for above ground tanks and larger capacity requirements. The construction experience related in this paper comprises the excavation of more than 80 storage facilities (total capacity 90 million bbl) for crude and refined products ranging from propane to heavy fuel oil. This paper also deals with the experience gained as well as the problems derived from the utilization of these oil storage facilities.

Jan 1, 1981

By T. Ritzel

Predictive maintenance technologies including vibration analysis, tribology, infrared thermography, ultrasonic detection, and electrical measurements have been applied to large electric mining shovels at Cyprus Sierrita. The predictive program was initiated by Cyprus Sierrita and P&H Mining Equipment at the Cyprus Sierrita Mine in Tucson, Arizona during August of 1996 on the P&H model 2300 and 4100 electric shovels. The utilization of these technologies has shown the potential for improving electric mining shovel availability and minimizing maintenance costs. Predictive technologies provide the tools to assess machinery condition. Availability is enhanced by the condition based planning of component replacement. Maintenance costs are minimized by focusing resources through condition based prioritization.

Jan 1, 1997

By T. Eggenberg

Mechanization and automation of logistic equipment has become one of the main key factors in raising productivity and competitiveness especially for complex and larger mining or tunneling projects. The Lake Mead Intake Tunnel #3 shaft mucking installation is a good example to demonstrate the potential that is found in an overall optimized logistic. It starts with the planning and results in using customized installations which fulfill the specifically defined requirements for the project. Rowa developed a solution and supplied a shaft mucking system using a discontinuous double drum hoisting concept with shaft buckets, loading, and unloading devices. With this fully automated system a continuous muck flow of 437t/h can be achieved.

Jan 1, 2010

By C. V. Trang, V. T. Le, K. Enns, J. J. Byerley

The precipitation characteristics of copper and nickel cyanides from solutions continuing copper zinc and nickel cyano complexes are examined. Equilibrium precipitation calculations are presented as well as comparative experimental data. The practical significance of the precipitation data is discussed in the co·ntext of an initial step m an overall treatment strategy for mixed cyanide effluents.

Jan 1, 1998

By J. G. Groppo, B. K. Parekh

Column flotation testing was conducted on the flotation feed slurry obtained from a preparation plant located in the Southern Illinois coal basin. The column flotation tests were conducted using three different bubble generating devices: a static sparger, a gas saver and a foam jet. Each of these devices was tested with three different types of frother and various column operating variables to provide maximum combustible recovery, minimum product ash and maximum pyrite rejection. The results show that column flotation provided improved flotation performance, in terms of combustible recovery as well as ash and pyrite rejection, for each of the bubble generating devices. However, the effectiveness of each bubble generating device was dependent on the type of frother used. Alcohol frothers were most effective for use with the static sparger, somewhat less effective for the foam jet and ineffective for the gas saver. Glycol frothers were effective for all three bubble generating systems, providing high combustible recovery (>90%); low clean-coal ash (4-6% ash) and high pyrite rejection (70-80%).

Jan 1, 1994

By J. A. Marshall

"INTRODUCTION The purpose of this paper is to investigate the potential for use of UAVs in underground mines and present a prototype design for a novel autorotating UAV platform for underground 3D data collection. The mining industry has recently shown increased interest in the use of unmanned aerial vehicles (UAVs) to assist in everyday operations [20, 11, 4]. Above ground, small UAVs are in some cases a more efficient, inexpensive, and safer alternative to manned aircrafts currently used for photography, inspection and security [6, 10]. For example, attaching camera, infrared and LiDAR payloads, UAVs can provide a low-cost method of obtaining highly accurate 3D photogrammetric data and aerial photography. UAVs are now commonly used in open pit mining operations for applications that include stockpile surveying, 3D pit modelling, facilities management, accident reporting, progress monitoring, and environmental assessment [11]. There are numerous companies offering UAV services for mining applications; e.g., UAV Geomatics, Leica Geosystems, Sky Futures, SenseFly and FlyTerra, to name just a few. Common services include stockpile and open pit volume computations, environmental assessment, aerial mapping and photogrammetry. Although the aforementioned services are thosemost commonly provided by UAV surveying companies, they may also add value to other daily mining operations. For instance, SenseFly offers pre and post-blast monitoring in order to identify the presence of misfires and wall damage. This data can also be used to reconcile the blast results with expected results. GEM Systems offers a UAV equipped with a magnetometer for mineral exploration surveys. Companies such as Barrick have even used UAVs for solids modelling at tailings dams and stability monitoring [11]. UAVs in mining have so far been mostly limited to surface applications. Harsh underground environments pose many obstacles for flying UAVs. The confined space, dampness, reduced visibility, air movement, and lack of control signal propagation hinders most operators from being able to fly a drone underground. It may be that truly practical uses for UAVs underground will require either autonomous or semi-autonomous flight capabilities. Although there are many difficulties with flying underground, the potential benefits from a working system could greatly improve mining operations. The potential benefits of deploying UAV platforms underground include access to unreachable and dangerous locations and removing personnel from unsafe situations. These benefits have the potential to greatly improve mine monitoring and mine safety. Research has shown that current UAV technologies exist that allow for autonomous indoor flight. Extensive research has been done to develop UAV systems that are capable of performing on-board simultaneous localization and mapping (SLAM), which can allow them to navigate and map a foreign environment autonomously [5, 7, 1, 13]. Grzonka [7] successfully used an open hardware quadrotor to autonomously navigate and map an office building. The research outlines the localization, mapping, path planning, height estimation and control of the autonomous quadrotor. Other research has been done that exploits autonomous UAVs for search and rescue. Kassecker [9] proposed a software and hardware framework for a quadrotor capable of indoor and outdoor urban search and rescue and Rudol [19] developed a system for human body detection and geolocalization using an autonomous UAV.The use of autonomous UAVs in search and rescue has the potential to improve situational awareness and surveillance for a rescue team. Similar research has been done that uses autonomous UAVs for indoor exploration. Pravitra [15] outlined a strategy for autonomous exploration of miniature air vehicles (MAVs) within indoor environments and Rudol [19] developed a method for using an unmanned ground vehicle (UGV) and a UAV for cooperative indoor exploration. These studies show that aut"

Jan 1, 2017

By R. Schlüter

"The global mining industry is facing increasing challenges in terms of geological, technological and social aspects. Potential exploi-tation of deposits shows a tendency to increasing depth with complex ores and decreasing grades. A promising approach to deal with these constrains is by applying alternative extraction methods like (bio-)hydrometallurgy as in-situ leaching (ISL) technology. The Bergakademie Freiberg University of Mining and Technology established the “Biohydrometallurgical Center for strategic Elements” (BHMZ) to foster the interdisciplinary research along the entire biohy-drometallurgical process chain to extract indium from sulfide ores. The involved Department of Underground Mining Methods deals with the design and implementation of a pilot-scale underground testing facility for microbial in-situ stope leaching in its “Research and Educational Mine”. This paper discusses the potential of in-situ bioleaching under technological aspects. In addition, different conditioning approaches based on hydraulic and explosive methods for enhanced permeability in the formation are introduced and the gathered data will be presened. INTRODUCTION A reliable, substantial and sustainable supply of raw materials is of crucial importance for any industrialized country. This dependency applies to “strategic elements” including rare earth elements (REEs), platinum group metals (PGMs) as well as a variety of other metals like indium and germanium which are needed for high-tech industry and products such as electric and electronic devices, fibre optics and laser technology (Barakos et al., 2016; European Commission, 2010). Due to the economic growth of the BRIC-countries (Brazil, Russia, India, China), the resource policy of China as well as the volatile world mar-ket prices of different metals the availability of these critical raw materi-als and therefore the dependency of the high-tech producing countries has become increasingly important (Barakos et al, 2016). Adequate supply is often affected by the increasing depth of de-posits, lower metal concentrations and more complex ore mineralogy. In addition, mining activities are increasingly restricted by their envi-ronmental and social impact and footprints. As a consequence, con-ventional mining and processing methods are limited by high energy consumption and technical constraints."

Jan 1, 2018

By W. J. Schlitt, K. McNaughton

A heap-leach field test was conducted during the 1993-1994 winter season at Carmacks, Yukon Territory, Canada. The purpose of the test was to demonstrate the viability of heap leaching Carmacks oxide copper ore in an arctic setting on a year-round basis. The test itself utilized a 5-m-diam crib loaded with 250 t of composite ore from the Carmacks copper deposit. The ore was stacked to a total height of 7 m in the crib, including 1 m of ore as an over- layer above the emitter system. This matched the plan for the commercial heap at the time when the test was started. The design also replicated an interior segment of the commercial heap. Leaching was done at a flow rate of 0.2 L/min/m2 using leachate at 21 °C. This temperature was maintained with no external heat input other than normal process heat transferred from electrowinning to the leachate via solvent extraction. Winter conditions were quite typical of those expected at the mine site. The temperature reached -54°C, while averaging -13°C over a three-month period. In spite of some flow system problems, leaching continued unabated, and freezing was limited to the insulating ore over-layer and isolated points near the outer crib walls. Thus, the test demonstrated that year-round heap leaching of Carmacks copper ore is practical in an arctic setting.

Jan 1, 2000

By Rod A. Levander, Kenneth B. King

INTRODUCTION The Panna Maria Uranium Project is located in South Texas, between San Antonio and Corpus Cristi, approximately 10 kilometers (6 miles) north of Karnes City, Texas. The tailings disposal facilities are located immediately south of the mill area and the central portion of the west pit. The mine and mill drainage pond is located north of the tailings pond. Location of the facilities is shown in Figure 1. The tailings pond is a disposal area for mill process wastes and has a capacity for storage of approximately 9 million metric tons (10 million tons) of tailings. This capacity is adequate for approximately 10 years of milling at a maximum rate of 2,700 metric tons (3,000 tons) per day. The tailings disposal facilities were designed to essentially eliminate discharge of contaminated waters to preclude degradation of surface streams or ground water. Water levels in the ponds will be maintained. through reuse in the mill and by evaporation. WASTE CHARACTERISTICS The sources of waste that is stored in the tailings pond include runoff from the mill area and tailings from the mill processing. The tailings consist of a sand slime slurry; the percentage passing the No. 200 sieve varies depending on the ore material, and it is generally in the range of 10 to 25 percent. The tailings have a density of approximately 1.2 metric tons per cu m (75 lb per cu ft) and an average specific gravity of 2.55. The liquid effluent from the mill consists of waste solutions from the grinding, leaching, extraction, and washing circuits of the mill. These solutions have an initial pH of 1.5 to 2.0 and contain the remnants of the leaching agents used in the mill process, sulfates, some silica as the primary dissolved solid, and trace quantities of soluble metals. This liquid is discharged with the solids into the tailings pond and is diluted by rainfall and runoff from the tailings dam. Runoff from the mill area, drainage from the mine area, and de-oiled water from truck washing facilities is discharged into the mine and mill drainage pond. Runoff from the mill area drains approximately 28 hectares (70 acres) from offices, shops, the mill site, the ore pad, haul roads, and adjacent areas. Mine drainage is collected in the mine area and pumped to the mine and mill drainage pond.

Jan 1, 1980

By Gerald L. Dollinger, Joseph A. Roby, David Krauter, Kenneth Deering

Three high performance TBM's equipped with large diameter (483mm) disc cutters are currently operating in Norway. This paper summarizes the design philosophy, field performance and ongoing technical development of these cutters. Included are discussions of the early problems encountered with their usage and the solutions to these problems that have been developed. Also included are discussions of the penetration rates and cutter usages observed. From this data it is concluded that high performance TBM's with large diameter cutters can produce significant improvements in both overall performance and in cutter costs under hard rock conditions.

Jan 1, 1991

By Chris Crowl

Employee involvement does not directly correlate to performance improvement. A key ingredient is the introduction of new Human Resource Systems that promote both performance improvement and employee involvement. Many organizations have tried to use employee involvement as the ''fixer" of performance issues-and seen their performance deteriorate further. They failed to realize that the entire human resource strategy must be connected to the goals of performance improvement and that greater employee involvement is only one tool in that strategy. So what are Human Resource Systems? These are systems that all managers use to get work done. Most of us are familiar with basics such as planning, assigning work, checking progress (auditing), completing assignments. We also commonly think in terms of staffing, training, compensation, or corrective action. All of these are human resource systems. All must be designed to support what you are trying to accomplish with your people. We call that the Human Resource Strategy. Let's examine one part of a total strategy intended to support more employee involvement at Kennecott Utah Copper-the hourly job structure. The design of hourly jobs directly affects how many employees of different capabilities are required to get the work done. It begins to answer some fundamental questions: • What are the roles and accountabilities of each employee? Do they have enough information to make decisions, to take responsibility for their work?

Jan 1, 2004

By Eduard Hamm

The main reasons for the development of higher heat levels in German coal mines are the increasing depth of working with the con- sequent higher rock temperatures, increased use of electrical equipment, and increasing coal output due to concentration and mechanisation of workings. In place of the normal decentralised underground cooling plants, schemes and pilot plants have been developed to produce the required cooling capacities in central air cooling units, which then supply the cold air to the underground working points where needed.

Jan 1, 1980

By M. J. Hughes

Kaiser Steel Corporation's Eagle Mountain operations are located in Southern California at a distance of about 130 miles east of the Corporation's steel plant at Fontana, California, and at a distance of about 225 miles from the nearest harbors which are located at Long Beach and Los Angeles, California Although the Eagle Mountain ore bodies are strategically located with respect to the steel plant and the harbor facilities, they are not of a very high grade and 'the geologic nature of the deposit makes it very difficult to mine and to concentrate. The iron ores occur as partial replacement of older zones mainly within dolomites and to a lesser extent within quartzites and quartz monzonites. The alteration was extremely variable and generally resulted in the formation of pyritic magnetic which, in part of the ore body, was leached to remove the pyrite and change the magnetite to hematite. Although the overall ore body is large, a major portion of it contains sulfur in the range of 1.0% to 5.0%. Obviously, this is too high a sulfur content for direct use in blast furnace feed.

Jan 1, 1968

By D. L. Kowal, P. J. Whittaker, M. A. Tuzun, N. O. Lotter

The area of flotation testing of drill-core is important in the business plan of most mining companies. Metallurgical information derived from this practice can be used to advantage in strategic decision-making. Sampling, flotation testing and subsequent Qem SCAN analysis of a mineral resource is one example of this approach. Anew resource, located in Sudbury, Ontario, is being assessed for the Sudbury Operations of Falconbridge Limited, which includes the Strathcona Mill. In this case, it was possible to improve the value of information from sampling and flotation testwork by using an improved, statistically-based test design, by sampling the resource by generic end-member ore type, and by integrating the Mineral Processing and Mineral Science disciplines into a Process Mineralogy team. In addition to producing standard metal grade and recovery information, this new approach provides more reproducible information from representative samples and flotation testing in a replicate format. Qem SCAN technology is used to produce a size by size mineral balance, including both modal percentages and liberation, from which flotation models for each ore type can be developed. As a result, a key understanding of the potential behaviour of a given ore type, if mined and then processed at the current mill operation, is gained at the 95%confidence level. The three ore types of this mineral resource were shown to have different flotation characteristics. Quantifying the mineralogy and liberation in each of the three ore types, has shown that this difference is due to changes in modal percentages of ferro-magnesium and magnesium silicate minerals such as pyroxene, talc and serpentine. Liberation across the three ore types is very similar and is therefore not responsible for variation in flotation performance.

Jan 1, 2003

By L. B. Kirk, A. R. Kirk

At New World, Au-Cu-Ag mineralization occurs in stratiform car-bonate-hosted, massive sulfide-iron oxide, and skarn-replacement deposits. Regional pyritic-alteration, local massive sulfide mineralization and mine wastes generate acid drainage within the district. Water quality improves down gradient through dilution and mixing of acid and metal-rich mine water with bicarbonate-rich, low-metal surface and groundwater, and precipitation of metal-rich ferrihydroxide phases. Natural deposits of ferricrete indicate that pre-mining ARD has occurred, providing important clues to pre-mining water quality. The geoenvironmental model identifies the Cu-skarn mineralization as the primary target for ARD management. Closure success will be limited by the geoenvironmental nature of the natural mineralization.

Jan 1, 2004