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By M. Ataei, F. Sereshki, R. N. Masir

Given the inherent risks and disruptions in underground coal mining operations, strengthening the resilience of critical infrastructure has become a vital priority. This paper aims to evaluate the resilience of the underground coal mining environment using historical data and expert judgment. The study serves as a framework for optimising the utilisation of critical infrastructure to minimise operational disturbances. To achieve this, a practical methodology has been developed, incorporating nearly two and a half years of collected operational data, a hierarchical structure, and a systematic approach. Furthermore, a case study is conducted to demonstrate the real-world applicability of the proposed method. Finally, the resilience index isintroduced as a straightforward summation of ranked impact factors, providing a clear metric for resilience assessment.

Dec 15, 2025

By Arturo Mauricci

El reencauche de neumáticos es un proceso que consiste en adicionar, previa evaluación y reparación, una capa de caucho al casco original, de manera que se pueda reutilizar y evitar consumir uno nuevo. Si bien este proceso no es una práctica común, pues se tiene la creencia de que no es rentable, en Minera Las Bambas se viene implementando con éxito. En el 2017, para una flota de 44 camiones Komatsu 930, se desecharon 542 neumáticos en la medida 53/80 R 63, mientras que en el 2018, al reencauchar 130 neumáticos, se desecharon 187 neumáticos menos, equivalentes a 654.5 toneladas anuales. Esto, replicado por los 30 años de estimado de vida de la mina, resulta en 19 635 toneladas menos de desechos contaminantes, con lo que se logra una reducción considerable del impacto en el medio ambiente.

Sep 20, 2019

By D. L. H. Forbes

(New York Meeting, February, 1912.) Introduction.. THE application of the cyanide process to complex sulphide ores for the extraction of their bold and silver is no longer a novelty, but, as an example showing modern tendencies in this direction, the following description of the new milling process at the Lucky-Tiger mine is offered: The extraordinary richness of the ore in the upper workings of this mine made any thought of milling in its early hays seen unnecessary. Its location in an almost inaccessible part of the rugged mountains just south of the Arizona boundary-line, and 60 miles from the town of Douglas, made the expense of bringing in machinery and supplies a very serious consideration. But, after the property had been shipping high-grade ore on mule-back for a few years, there remained in the mine a considerable tonnage of vein-matter that was too low in value to ship, but which it was thought could be milled near the mine at a profit. The first milling-experiment consisted in the installation of Nissen stamps in conjunction with concentrating-tables and Frue vanners, but, as the ore from the upper workings contained most of its silver in the form of cerargyrite, this type of mill was not successful. The proximity of the mine to the great copper-concentrating mills of Cananea and Moctezuma naturally made the influence of copper-milling, ideas felt in the company's next installation. At considerable expense a stage-crushing concentrating-mill, with a capacity of 100 tons per day, was built. This mill was modeled along the lines of the most approved practice in copper-concentrators at that time, the main idea being that crushing by stages in rolls was necessary in order to prevent losses from ?sliming." Largely owing to the fact that, when the mill

Aug 1, 1912

By Oliver Bowles

ROCK is no doubt the most abundant of all material things because the planet on which we live is made of it. All animal and vegetable organisms and the multitude of natural and manufactured products that occupy a comparatively insignificant film on the outer surface of the planet are derived from rock. Processes of Nature acting for untold centuries have transformed rock into soil, making possible the development of vegetable and annual life; and rocks have supplied the numerous raw materials, metallic and nonmetallic, wherewith the innumerable appurtenances of a complex civilization have been fabricated. As time goes on we live with increasing speed and with enlarged desires. Time and space are shortened by man's ingenuity, and products for human use must be manufactured with greater and greater celerity. It was inevitable that Nature's slow processes of rock alteration should fail to keep pace with human demands and that the variety of natural products should fall far short of the requirements of an industrial age. Man therefore supplemented these processes by attacking rock in its native bed amid using it to supply needs not otherwise satisfied.

Jan 1, 1934

When Caterpillar announced that it had purchased Bucyrus for $8.8 billion, it was billed as the next great chapter in the history of mining. Surely, when the history books are written, it will be remembered as a deal that changed the face of the mining equipment sector, and it could well be a major milestone in the path toward autonomous mining in the future. In the short term, the deal is a clear indication that the world?s largest equipment maker is bullish on the mining sector. The purchase of Bucyrus allows Caterpillar to expand its mining interest to six product segments (underground, surface extraction, large mining trucks, surface material handling, hauling products and growth markets) with 16 product lines to serve the mining industry. But the commitment doesn?t end there. According to Steve Wunning, president of Caterpillar?s resource industries group, which includes Cat?s global mining division, the commitment to mining goes far beyond the acquisition of Bucyrus.

Jan 1, 2011

By L. A. Stinnett

An investigation of hazardous surface openings of abandoned and inactive underground mines in the Black Hills area of South Dakota has revealed: (1) tracing legal ownership of mineral claims via county courthouses is confusing, complex, and oftentimes misleading, (2) in general, the selected mine openings in this investigation are to be considered relatively high in risks and hazard potential which poses a threat to the general public, (3) mine closure procedures and designs can generally be categorically implemented depending on the overall situation of the particular mine opening with subsequent unit costs estimates, (4) few preventive state or federal legal measures exist to date concerning mine closures, and (5) liability damages relating to mine opening accidents usually involve expensive and complex common law cases.

Jan 1, 1979

By JOHN BUZARD

In the following pages the writer has endeavored to give an account of the many methods, advantages, and disadvantages of preparing and burning powdered coal. For much of the information jmparted the writer is indebted to various firms in the United States and Canada whose plants he visited, also to the technical press. Manufacturers and operators of coal-fired furnaces can not afford to disregard the possible advantages of pulverizing their coal before burning it. Hence the purpose of this bulletin will be fulfilled if it leads them, after making careful estimates, either to abandon their present method of burning cGal on grates or stokers, and install the pulverizers, conveying system, powdered-coal feeder, and burner best suited for burning powdered coal in their plant, or to reject, as uneconomical, the replacement of their present system of burning coal by a system for pulverizing and burning it. No research work on the combustion of powdered Canadian fuels has been carried out by the Mines Branch, Department of Mines; but if this research work were carried out scientifically by competent engineers, chemists, and physicists, it would show how powderedcoal furnaces and burners should be designed to gi ve an efficiency higher than they give at present.

Jan 1, 1923

By D. R. Wilburn

This summary of international mineral exploration activities for the year 2009 draws upon information from industry sources, published literature and U.S. Geological Survey (USGS) specialists. The summary provides data on industry exploration budgets by region and mineral commodity, identifies significant mineral discoveries and areas of mineral exploration, discusses government programs affecting the mineral exploration industry and presents analyses of exploration activities by the mineral industry based upon these data. Two types of information are reported and analyzed in this annual review of international exploration for the year 2009: 1) budgetary statistics expressed in U.S. nominal dollars provided by Metals Economics Group (MEG) of Halifax, Nova Scotia, and 2) information on regional and site-specific exploration activities that took place in 2009 and were compiled by the USGS. The MEG information summarizes planned company budgets for worldwide exploration activities in 2009, primarily for base metals (copper, lead, nickel and zinc), diamond and precious metals (gold, platinum-group metals and silver). Information on uranium exploration was included in the MEG overview for the first time in 2007, although this information was not included in the USGS analysis prior to 2008. The MEG survey methodology was changed in 1999 to include companies with exploration budgets greater than $100,000, as well as those companies included in prior studies whose anticipated budgets were above $2.9 million. MEG estimates that its post-1999 surveys cover at least 90 percent of world nonferrous nonfuel mineral exploration budgets. The 2009 survey is reported by MEG to cover an estimated 95 percent. Companies who chose not to participate in the MEG study, private companies that do not publish data and government-funded exploration activities make up the majority of the remaining 5 percent. MEG included 86 more companies in its 2009 survey than it did in 2008.

May 1, 2010

By S. Hamilton

Occurrences of boron-containing ores are relatively rare on a global basis. The first verifiable use of borax was in the 8th century by Arabian gold and silversmiths. Due to the rarity of the borate mineral occurrences, borates were originally traded at relatively high prices and were used for very specialized applications. Today, there are

Jan 1, 2006

By C. R. Landis

The Wyoming bentonite industry finished 2005 with strong growth. For most of the markets, demand exceeded supply. The industry continues to be heartened by the strength of its longtime markets, oilfield and iron ore pelletizing markets. But overall, all of the major markets enjoyed good to excellent commercial conditions. Growth at the macroscale was fueled by the continued strong domestic economy, by the exchange rate of the U.S. dollar in global markets and by strong worldwide global demand. As result, two new greenfield operations are in the early stage of development in the Wyoming region for the first time in more than two decades.

Jan 1, 2006

By Jian Wang, Xiaoming Sun, Ming Jiang, Fuxin Shen, Chengyu Miao, Wenchao Zhao, Yong Zhang

The increased thickness of the coal seam leads to higher goaf roof collapse height. In contrast, the dynamic pressure from the mining of ultra-thick coal seams generates higher abutment pressures around the mined area and may affect the stability of roadways servicing these panels. To mitigate the deformation and damage issues in the roadways during the extraction of ultra-thick coal seams under a high depth of cover, researchers have proposed combining high prestress constant resistance support and roof-cutting technology (HPCR-RC). The deformation and failure mechanisms of the roadways during the extraction of ultra-thick coal seams under a high depth of cover, along with the mechanisms and field control effects of the combined support system, have been analyzed through theoretical analysis, numerical simulation, and field experiments. The research findings reveal that the high in situ stress, initial excavation disturbance, rotation, and subsidence of the fractured roof of the extra-thick coal seam led to significant deformation and damage in the roadways. High prestress constant resistance support compensates for the initial stress loss, reduces initial stress concentration, and absorbs deformation energy. Moreover, the roof-cutting technology severs the connection between the goaf roof and the roadway roof, disrupts the path of stress transfer, raises the level of roof backfilling in the goaf, and provides support to the roof, effectively alleviating the pressure on the coal pillar ahead and adjacent to the working face. Field experiments have confirmed the effectiveness of HPCR-RC, as indicated by a substantial decrease in surrounding rock deformation and support pressure within the roadways.

Sep 25, 2023

By Sean McClenaghan

Significance Setting Size Production Value History of Discovery Zn and Pb at Austin Brook Brunswick Belt Exploration Discovery Hole Geology Structure Metal Zonation Directed Research Incremental Ores Precious metals Closure and Beyond Mining Remnants Tailings

May 1, 2013

By D. Marcotte, R. V. Dutaut

In most exploration or mining grade data-sets, the presence of outliers or extreme values represents a significant challenge to mineral resource estimators. The most common practice is to cap the extreme values at a predefined level. A new capping approach is presented that uses QA/QC coarse duplicate data correlation to predict the real data coefficient of variation (i.e., error-free CV). The cap grade is determined such that the capped data has a CV equal to the predicted CV. The robustness of the approach with regard to original core assay length decisions, departure from lognormality, and capping before or after compositing is assessed using simulated data-sets. Real case studies of gold and nickel deposits are used to compare the proposed approach to the methods most widely used in industry. The new approach is simple and objective. It provides a cap grade that is determined automatically, based on predicted CV, and takes into account the quality of the assay procedure as determined by coarse duplicates correlation.

May 1, 2021

By R. A. Thomas, C. D. Litton

"The objective of this study was to develop a laboratory-scale method to rank the ignition and fire hazards of commonly used underground mine materials and to eliminate the need for the expensive large-scale tests that are currently being used. A radiant-panel apparatus was used to determine the materials’ relevant thermal characteristics: time to ignition, critical heat flux for ignition, heat of gasification, and mass-loss rate. Three thermal parameters, TRP, TP1 and TP4, were derived from the data, then developed and subsequently used to rank the combined ignition and fire hazards of the combustible materials from low hazard to high hazard. The results compared favorably with the thermal and ignition hazards of similar materials reported in the literature and support this approach as a simpler one for quantifying these combustible hazards. Resumen ¦ El objetivo de este estudio fue el desarrollo de un método a escala de laboratorio con el fin de clasificar los peligros de ignición y fuego de materiales comúnmente usados en minería subterránea y la eliminación las pruebas costosas y a gran escala que se realizan actualmente. Se usó un aparato de panel radiante con el fin de determinar las características térmicas relevantes de los materiales: tiempo de ignición, flujo de calor crítico para ignición, calor de gasificación y tasa de pérdida de masa. Se derivaron tres parámetros térmicos de los datos: TRP, TP1 y TP4, luego fueron desarrollados y subsecuentemente usados para clasificar los peligros combinados de ignición y fuego de materiales combustibles, de bajo riesgo a alto riesgo. Los resultados tuvieron una comparación favorable con los riesgo/peligro térmicos y de ignición de materiales similares reportados en la literatura y apoyan este enfoque como uno más simple para la cuantificación de estos riesgos combustibles"

Jan 1, 2015

By Felipe P. D. Lopes, Caroline G. de Oliveira, Sergio N. Monteiro, Lucas A. Pontes, Janine F. de Deus

For decades, natural fibers have been studied as an economical and environmentally viable alternative to use instead of some types of synthetic fibers, for example fiberglass. To find the best way to make composites, the investigations shall be under various configurations, which is extremely important to understand the potentialities and facilities. To aim the comparison of impact performance of epoxy matrix composites reinforced with ramie fabric, the composites were produced by two different methodologies: under pressure and vacuum. The results show that the composites produced under pressure have greater resistance to both the Charpy and Izod Impact than under vacuum conditions.

Mar 1, 2018

By Roque Benavides

El artículo describe el enfoque de minería comprometida con el desarrollo sostenible de Compañía de Minas Buenaventura, el mismo que está basado en cuatro importantes pilares: fortalecer las actividades tradicionales a las que se dedican las comunidades vecinas; impulsar con ellas una “hermandad del agua” para obtener y compartir este valioso recurso; fortalecer la educación y la salud como estrategia para potenciar capacidades individuales y colectivas; y velar por la vida de sus colaboradores, aspecto en el cual la innovación y la tecnología juegan un rol muy importante. Adicionalmente, el autor destaca el rol solidario y reactivador de la industria minera en el marco de la emergencia nacional por COVID -19.

Jul 30, 2020

By Serdar Aktaş, Burcu Nilgün Çetiner

According to critical statistical studies, antimony is one of the rarest elements in the world, and global resources could be exhausted by 2050. In light of these observations, its extraction will be costly due to poor-quality ore, deep mining, remote locations, and high energy consumption. In the present study, an alkaline leaching process was carried out on stibnite concentrate to evaluate the effect of reaction parameters on the percentage of antimony extraction. The leaching efficiencies of different sulfur and hydroxide sources were studied and compared to one another to create a better understanding of the reaction process. Kinetic models were investigated to identify the reaction pathway and calculate the activation energy. The activation energy of the stibnite dissolution was assessed as 19.13 kJ/mol using a two-dimensional diffusion-reaction model. The value of activation energy indicates the quantity of energy necessary for a reaction to proceed. As expected, potassium hydroxide leaching was significantly more successful than was sodium hydroxide; however, in terms of economics, the use of sodium hydroxide was found to be more cost-efficient. Interestingly, this finding indicated that caustic leaching is still the most effective method for stibnite extraction.

Jul 23, 2020

By D. M. Schubert

As a clean and renewable energy carrier, hydrogen is an important component of most alternative energy portfolios. Hydrogen combines very high energy content by weight with excellent environmental attributes. Since hydrogen reacts with oxygen to produce only water with release of energy, it can be used to power fuel cells, combustion engines, and turbines, without production of greenhouse gases at point of use. However, because of its low volumetric density, storing pure hydrogen is impractical. Thus implementation of hydrogen technologies requires materials that can safely store and release large amounts of hydrogen (1,2). In recent years, the U.S. Department of Energy (DOE) and other governmental agencies around the world sponsored extensive research on hydrogen storage materials, including those based on boron. These efforts have resulted in significant advances in hydrogen storage technologies. Boron materials stand out as leading candidates for hydrogen storage among the many options investigated. Combining excellent hydrogen densities, release rates, and safety characteristics, some boron materials can hold substantially more hydrogen by weight and volume than even pure liquid hydrogen (3-5).

Jan 1, 2010

By Benjamin Smith Lyman

PAGE I. ANCIENT HISTORY,........... 57 Accepted Fables ; Babylonian Mapping ; First Surveying. II. COMPASS,.............59 Chinese Invention; Marco Polo; First European Compasses ; Early Knowledge of Variation ; Plotting with the Compass ; Hanging-Com pass ; Supposed Gravitational Error ; Merit of the Compass. 111. Telescope,............63 Origin (Roger Bacon, Porta, Digges, Lippershey, Galileo) ; Improvements (Micrometer and Cross-Hairs, Rittenhouse's First Telescope, Platinum Cross-Wires, Telescopic Sights, Reflecting Telescope, Achromatic Lens, Kellner Lens in Erecting Telescope, Inverting Telescope). IV. Theodolite,.............81 Origin ; Derivation of the Name. V. TranBit,.............86 First Surveying Transit; Edmund Draper. VI. Instrument-Parts,..........89 Ramsdenl a Dividing Engine ; Fineness of Graduation ; Conical Gradua tions ; Full Vertical Circle ; Leveling-Screws ; Shifting Tripod-Heads ; Hoffman-Harden Tripod-Head ; Heller & Brightly's Improvements. VII. OTHER INSTRUMENTS AND APPLIANCES,......100 Sunflower; Plummet-Lamp; Chains and Tapes. VIII. SCOTT'S TACHYMETER,.........104 IX. Nomenclature and Classification,.......105 Names; Grouping. Surveyors are much indebted to Mr. Scott for so vigorously attacking the subject of the origin and history of mine-surveging instruments, the compass, the telescope, the transit and other apparatus. He is not afraid of the dark, nor yet foolishly bashful in broad daylight. He does not recoil from the obscurities of the earliest times and the most difficult historical points; and, with commendable public spirit, he makes his own invention known to his fellow-workers, and challenges their criticism. He has, moreover, elicited the praiseworthy emula-

Jan 1, 1902

By N. Katsikaros, A. Lewis-Gray, P. Richards

"To optimize gold recovery in complex leach-to-electrowinning processes, Gekko Systems developed the Gekko resin exchange column (G-REX) as an intermediate step, using a highly gold-selective resin to isolate contaminant metals. The AuRIX®100 resin produced by Purolite is licensed exclusively to Gekko, with the G-REX column designed specifically for this resin. Operational experience has been gained at the Castlemaine Goldfields Ballarat gold mine. In near-continuous operation since 2008, the Ballarat plant treats unclarified concentrate leach solution. The extension of this technology to higher throughputs and more complex chemistry is discussed.RÉSUMÉ Afin d’optimiser la récupération de l’or dans des procédés complexes impliquant la lixiviation suivie de l’extraction électrolytique, Gekko Systems a développé la colonne Gekko de résines échangeuses d’ions (G-REX) comme étape intermédiaire, à l’aide d’une résine hautement sélective pour la récupération de l’or qui permet d’isoler les métaux contaminants. Gekko détient la licence exclusive pour la résine AuRIX®100 produite par Purolite, et la colonne G-REX a été spécifiquement conçue pour cette résine. C’est à la mine d’or Ballarat de Castlemaine Goldfields que l’expérience opérationnelle a été acquise. L’usine de Ballarat, en exploitation quasi-continue depuis 2008, traite une solution concentrée non clarifiée de lixiviation. L’extension de cette technologie à des capacités supérieures et à une chimie plus complexe est examinée.AURIX®100 RESINAuRIX100 resin is a crosslinked polystyrene alkaline resin developed by Henkel (Virnig, Mackenzie, & Adamson, 1996). The resin beads are off-white in colour and spherical, with a nominal size of 100% +600 µm. This resin is highly selective for gold and silver over many metals, by way of extracting precious metal–cyanide complexes from leach solutions with a pH of less than 11.5. The higher end of the pH scale produces the best selectivity according to the order of preference: Au > Ag > Hg > Zn > Ni > Cu > Co > Fe. Purolite produces the resin and Gekko Systems maintains licensing of AuRIX100 resin for use in its G-REX column, as part of its unique suite of gravity gold–handling equipment.Significant cost savings over carbon-in-solution (CIS) systems are realized with AURIX100 resin: approximately 4–12% in capital savings and 27–40% in operating costs (Virnig, Mackenzie, Katsikaros, & Gray, 2004). Additionally, AuRIX100 resin is not susceptible to fouling; that is, the resin does not load with inorganic salts or organic compounds that would affect the loading and extraction of precious metals. To counter any potential for fouling by inorganic salts, a dilute acid wash is periodically conducted in service on the resin to unblock resin pores."

Jan 1, 2017