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By T. Owen

Not since 1917 has a foreign company developed a standalone, grass roots gold mine in Russia. With. Russia's political changes of the late 1980s, development of mineral prospects once again beckons foreign investors. In 1990, Cyprus Amax began aggressively searching for such an opportunity. Early in 1997, production will commence at the Kubaka gold project located in the Russian Far East, near the Arctic Circle. The Kubaka project is a 1,750-tonne per day open-pit operation that will produce more than 300,000 ounces of gold per year. This paper discusses the challenges of locating such a prospect, doing business in Russia, developing supply lines, identifying work force capabilities, gaining government approvals, securing financing, arranging for gold sales and ultimately building a facility in this arctic region.

Jan 1, 1997

By William Gleason

"Once the primary fuel source for the United States and the economic backbone for communities from Appalachia to Wyoming, coal has been on a steady decline since the mid 1990s, and is now at the center of political debate in the United States.The political spectrum of the United States is divided on the future of coal and its place in the energy sector. The coal mining industry and the communities that rely on coal have increasingly been pitted against forces that wish to regulate coal to the history books.In 2008, President Obama launched what many have called his war on coal, and during his eight years in office, he pushed through numerous pieces of regulations and legislation and that he said were aimed at reducing carbon emissions, but that others viewed as direct assaults on the domestic coal industry. Obama led the United States delegation to Paris to sign the Paris Accord in 2016, a 196-country agreement pledging that the United States would do its part to reduce carbon emissions. His administration also instituted clean air, power and water regulations that added extra environmental burdens to many industries, but perhaps none more so than the coal industry.In this month’s lead feature, “A study of U.S. coal mine closures since 1994” (page 18), the impact of the war on coal, and other factors, can be seen in text and figures. Author Jacob Brinkman and coauthors Jay Schafler and Catherine Johnson scoured the data of the U.S. Energy Information Administration (EIA) and the U.S. Mine Safety and Health Administration (MSHA) to show how coal production and mines have been impacted since 1994 and how the years 1994 to 2000 and 2008 to 2016 were particularly hard on the industry.For example, in 1994 there were 2,354 coal mines in the United States. Currently, there are 1,035 mines in operation.In 2016, then candidate Donald Trump promised to end the war on coal and to put coal miners back to work. In 2017, President Trump has followed up on those promises. He announced plans to withdraw the United States from the Paris Accord, signed an executive order designed to undo the Clean Power Plan put in place by President Obama, halted the research on the health effects of mountaintop removal coal mining, directed the U.S. Environmental Protection Agency (EPA) to revise the guidelines of waste water from power plants and has touted that more than 1,000 coal miners have returned to work since he was elected."

Jan 9, 2017

The Black Hills Mineral Atlas briefly summarizes all pertinent date available on the mines and mineral deposits in the Black Hills that have been explored, developed, mined, or located. The purpose of the atlas is threefold: First, from available date the general potentialities of the Black Hills region can be determined, although it is not possible to calculate actual ore reserves; second, it will provide the necessary basic information regarding a given property or commodity for further detailed study; and third, the compilation is a comprehensive directory of Black Hills deposits.

Jan 1, 1954

By Charles R. Keyes

the leaching of near-by rocks, had had no other result than to bring out from obscurity three certain features of practical lmport, all the labor of that controversy would have been well expended. These three points are : (1) a clear distinction between the vadose and the profound zones; (2) a determination of the manner in which the latter may be invaded by conditions of the former; and (3) an establishment of the general truth of the lateral-secretion theory when vadose conditions prevail, and of the. ascension-theory under profound conditions. In the practical consideration. of ore-deposits these generalizations are fundamental. Their wider application must be productive of great industrial advantages. Of first importance in the broader scientific survey of ore-genesis is the recognition of a sharp distinction between vadose and profound conditions. To many who listened to Professor Posepny's remarkable paper, read at the Chicago session of the Institute during the Columbian Exposition in 1893, this seemed, as Dr. S. F. Emmons has already observed, its most valuable and suggestive feature. Notwithstanding Posepny's implications to the contrary, and his vigorous berating of Sandberger's views, the immediate and lasting .effect of the . argument was really to strengthen greatly Sandberger's position. For it completely and sharply separated the lateral-secretionists from the ascensionists, raising the sphere of the former bodily above the line of permanent water-level and at the same time confining .the sphere of the latter to regions below that horizon. A little later, Professor Van Rise showed in some detail how meteoric waters may deeply invade the profound zone and carry vadose conditions into it. The zonal limitations of two great and apparently opposed agencies being thus definitely fixed, it is found that neither of the theories based thereon is susceptible of general application. If the generalizations of the lateral-secretionist be propounded solely for vadose conditions, we are able to agree with all of his more-important contentions; while there is general acquiescence in the views of the ascensionist if their application be restricted to the profound zone. Of the ore-bodies of the world that are mined to-day, the majority are essentially vadose in origin, and probably originated

Jul 1, 1910

By E Novikov, D Johansson, U Nyberg, A Beyglou, N Petropoulos

Fragmentation is an important factor for improving downstream processes in mine operations. Six trials have been conducted at the Aitik copper mine to investigate the effect of ultra-short inter-hole delay times, i.e. smaller than 1 ms/m of burden, on fragmentation. Swelling, MWD data, and crusher efficiency were also evaluated for trials. According to the results, the effect of examined short inter-hole delay times, i.e. 0.14 to 0.86 ms/m of burden, on fragmentation was found to be marginal. Delay time of 0.43 ms/m of burden resulted in slightly finer fragmentation and larger swell; however, the effect of short delays was overshadowed by the effect of small variations in specific charge.

Jan 1, 2014

By W. Geo. Waring

THE growing need of better methods for the recovery of zinc and other elements from complex sulfide ores has suggested an inquiry respecting a possible group separation of the elements by the aid of volatilization at more or less elevated temperatures. It 'is evident that if the zinc content of such ores can be completely separated, for instance, as pure oxide, by a volatilization 'method, there should be no difficulty in recovering the other elements by smelting and refining. Zinc burning" as applied to zinkiferous ores has advanced but little in practice since the invention of the wetherill grate-furnace process in 1852, as may be seen by reference to papers on the subject.' In other words the thermochemical reaction employed in effecting the volatilization of the zinc is essentially one of reduction by means of carbon, whether the ores treated contain their zinc in an oxidized form, or as the sulfide. The zinc vapors, liberated from the ores at a temperature above that required for the reduction of ZnO by C (about ,1100° C.) or for the volatilization of ZnS per se, (about' 1300°-1400° C.) are subsequently burned to ZnO or to ZnO + SOz, by contact with' atmospheric ,oxygen in the upper or posterior parts of the furnace chamber, or in a so-called "combustion chamber" after leaving the .furnace proper.

Jan 1, 1925

By Todd M. Ruff

Researchers at the National Institute for Occupational Safety and Health (NIOSH) are studying methods to prevent workers from being entangled in machinery used at mining operations. An analysis of mining accidents in the United States that resulted in a fatality or permanent disability from 2000 through 2005 showed 438 severe incidents that involved contact with machinery or equipment, an average of 73 per year. Researchers determined that the most common machinery involved in these severe accidents was conveyors. Also, a significant portion of the accidents occurred during machine maintenance and repair. Researchers are focusing on improved methods to prevent unintentional machine startup during maintenance activity and methods to detect workers near moving machine components. One new technology that shows promise for this application is intelligent video. Popular in the surveillance and security industries, these systems use cameras and computerized video analysis techniques to automatically detect the presence of people in preset zones within the camera?s field of view. A preliminary study has been initiated to determine if this technology could reliably detect the presence of workers in hazardous locations near machinery. Possible advantages of the use of this technology include improved detection zone demarcation and improved ability to distinguish between hazardous and non-hazardous proximity, compared to conventional proximity sensor techniques. Initial tests to detect a person near a conveyor system in daylight conditions showed promising results. A description of the technology, test procedures and results, implementation challenges, and future research needs are discussed.

Jan 1, 2008

By B. Calver, D. J. M. Farnsworth

"As open-pit operations expanded at Pine Point, hydraulic aquifer evaluation was undertaken to establish the criteria necessary for the design of a feasible dewatering system.The extreme climate of this northern location dictated that the ore zone under extraction be rendered as dry as possible to minimize freezing effects. The design and implementation of such a system necessitated detailed hydraulic evaluation, and the problems that occurred are typical of those inherent in open-pit mining operations in northern areas.The paper describes the problem solution as approached from a mine engineering point of view, with particular reference to the practical aspects of operation and installation. The hydrological analysis used is simple and readily applicable to most open-pit dewatering problems."

Jan 1, 1969

By W. A. Jones

Purpose of Paper Geophysics is a highly developed science which has found a wide use in industry. Perhaps the most spectacular application has been in the field of oil exploration. It has been estimated that, up to the end of 1939, geophysics was responsible for the discovery of five billion barrels of oil. In 1944, the sum o $40,000,000 was expended for geophysical work in the search for new oil deposits. Although the metal mining industry has so far made comparatively little use of the science, it is becoming increasingly common for the exploration engineer or geologist to be required to co-operate with the geophysicist. Many papers dealing with applied geophysics have been published but in most of them advanced training in physics and mathematics on the part of the reader has been assumed. It is difficult for the average engineer to obtain a ready understanding of the equipment, field procedure, and scope and limitations of the science from the literature. The present paper attempts to describe briefly and in simple terms the principles underlying magnetic, self-potential, and electrical resistivity methods and their application to a field problem. Introduction Geophysics is concerned with the study of gravity, magnetism, natural earth currents, earthquakes, vulcanism, and many other natural phenomena. The methods, originally devised for the measurement, for scientific purposes, of the forces associated with such phenomena have been adapted to the search for buried deposits of economic value. If the body sought has large dimensions and distinctive physical properties, geophysical measurements may reveal associated, and in some cases quite characteristic, anomalous features. However, in many instances the mass cannot be indicated directly but has a common association with geological features which can be defined by physical measurements. Although such surveys cannot specifically identify oil, metalliferous minerals, or other commercially valuable substances, it is possible to delineate anomalous sub-surface physical features which, with the help of geological information, can be assessed as possible or probable indications of the body or structure sought. The nature and extent of the material causing an anomaly, and its economic importance, can only be determined by further exploration, such as drilling.

Jan 1, 1947

By O&apos

Southern Ohio Coal Company (SOCCO) and the U.S. Bureau of Mines have identified techniques to optimize the use of scrubbers on continuous miners. The techniques provide maximum respirable dust control while maintaining a high output. The use of radio remote control and scrubber help to achieve greater advance between lifts by locating the operator in fresh air during the mining cycle. He is also kept away from newly exposed roof, which is not supported. An alternative to fan-powered scrubber was also evaluated at SOCCO. A high-pressure water-powered scrubber system eliminated the noise associated with fans, and achieved an intrinsically safe system. Experience in the use of these scrubber systems and remote control at SOCCO are discussed.

Jan 1, 1990

By Ben C. Gerwick

This publication is intended to document recent innovations and technologies that have the best potential for effectively improving the quality of marine foundations while reducing the cost, time and risk of construction. Marine foundations originated in Neolithic times with the Swiss Lake Dwellers who constructed pile-supported houses, safe from invading tribes. The Queen of Babylonia built the first recorded bridge in 1500 BC across the Tigris. The foundations were large flat stones laid on the river bottom. About the same time in India, builders extended their water well techniques to the construction of ?well? foundations in the beds of their rivers. These were really the first open caissons; brick walls were built up in a circular ring while divers excavated sand from the bottom, sometimes at a depth of 100 feet. The Romans extended the clay-filled cribs of the Middle East to shallow cofferdams, which they sealed by underwater concrete made with pozzolanic cement from Mt. Vesuvius.

Jan 1, 2013

By S. M. I Kytö, J .. K. Mäkinen, K. Saarhelo

"At the Outokumpu Oy Harjavalta Copper Smelter the control philosophy of the flash smelting process has been changed from the slow feed-back control to feed-forward control. This is important as the fluctuations in the flash smelting furnace matte grade and slag temperature are desired to be minimized.The system is based on a specially designed automatic sampling device and the Outokumpu Courier 20 on-stream X-ray fluorescence analyzer. A microcomputer-based Analyzer Operator Station (AOP) controls the system and calculates the process parameters for the furnace from the analyzed chemical composition and other existing data.A considerable reduction in the deviation of the matte grade and slag temperature has been gained. This has resulted in conservation of energy and refractories, lower copper losses and higher through-put in the flash smelting furnace and converters.1.0 IntroductionThe flash smelting technology for copper concentrates was developed at the Outokumpu Oy Harjavalta Smelter soon after the World War II. The incentive for this development was shortness and high price of any form of energy. The fact that smelting can be carried out autogenously, without external energy by utilizing the latent heat of sulfide combustion was known decades before, but Outokumpu Oy was the first company to take the advantage of this knowledge in practical operation. A further advantage of this technology was that the SO2 containing gases suited well for sulfuric acid production, thus minimizing the detrimental effects on the environment (1).The very heart of the flash smelting process is the reaction shaft of the flash smelting furnace (see Appendix I). Heating up of the dried feed mixture, dissociation of several compounds, ignition and oxidation of the feed take place very intensively in the reaction shaft during 2 - 3 seconds, which the fine grained particles reside in the reaction shaft. A very accurate control of the amounts of the feed materials as well as of oxidizing gases, fuel, etc. is of primary importance."

Jan 1, 1989

By P. Ravanal, J. Blazquez, F. Ortega, P. Couceiro, J. Navarro

Massive blasting technique is an interesting alternative to optimize mining’s performance by enhancing digging rates and overall operation’s activities, especially when a reduced operational bench width is available. The exploitation of a huge bench through multiple blasts would mean a potential reduction in productivity and higher operational difficulties. In such hard circumstances, combined with complex geotechnical conditions, a full ground vibration analysis for near and far field vibrations are required in order to safely design and conduct the blast. In this paper, a comprehensive case study will be discussed to show how the application of massive blasting techniques was safely implemented in very complex geotechnical conditions. The proposed solution was based on performing a full ground vibration study to optimize blast design parameters, such as charging and timing, in order to fire the complete bench blast in a single shooting event, without compromising the slope stability. Thus, a massive blast with an approximate tonnage of 6.0Mt was successfully designed and blasted, attending all safety and stability criteria defined by the geotechnical and drilling and blasting departments of Minera Escondida.

Jan 1, 2024

By J. L. Young

The McLaughlin Mill started operating in January, 1985. For the first eighteen (18) months start-up, initial operation, and circuit debottlenecking have been done. The mill was designed to recover gold from a refractory ore requiring acid autoclaving pretreatment. This paper discusses the problem associated with bringing this complex hydro-metallurgical plant to consistently achieve design tonnages. Also, briefly described are the mill flowsheet, training program, permitting, and process and project development.

Jan 1, 1987

By K. Howard Poulsen

Shear zones are tabular tructures which tend to occur either discordantly within, or concordantly along the margins of, competent rock masse uch as plutons, sill or flows. They contain deformed equivalents of their host rock and are common sites for gold mineralization localized in tructure oriented y tematically relative to the shear zones and internal linear fabric. Apan from genetic implications, hear zone analysis proves useful in exploration for this type of deposit because the zones are generally wider and more continuous than associated mineralization and because there is an element of predictability to mineralization geometry (i.e. vein orientation. plunge).

Jan 1, 1986

By C. Carrasco

Caletones Smelter, Division El Teniente of Codelco Chile, has used Teniente Converter (TC) as the only smelting unit since November 2000. The modernization project considered the shutdown of the last reverberatory furnace, the installation of the fourth Teniente Slag Cleaning Furnace, the installation of a new fluidized bed dryer and the modification of the concentrate injection system into TC. The modernization project and related investments allowed for the increase of the smelting capacity up to 1.25 million t of concentrate annually.Next stage of the smelter expansion in the year 2004 considered the increase of the smelting capacity up to 1.44 million t/year. The expansion required technology modernization and the installation of the new equipment, such as concentrate injection system, oxygen plant, fluidized bed dryer and storage bin. Currently the annual smelting capacity is about 1.35 million t of copper concentrate, being limited by sulphuric acid plant treatment capacity. This paper presents the technology and production evolution in the Caletones Smelter in the years 2000 - 2006, demonstrating the potential of development and competitiveness of Teniente Converter as world-wide recognized smelting/converting reactor.

Jan 1, 2007

By Martin Junker

This Notwithstanding all the debates on climate change and renewable energy, coal remains the world's no.1 primary energy source even in the 21st century. In 2011 alone, total output rose from 420 million t to around 6.6 billion t. Similar growth rates are also expected for the next few years. In order to meet demand, new seams are being tapped and others mined far more extensively. In most cases, this means a move from open-cast to deep mining, and extracting coal from ever greater depths. At the same time, extraction processes such as the room and pillar method are being replaced by longwall mining, which significantly increases seam yield and therefore output. The depth of extraction with new, modified mining methods is increasing rapidly around the world - in most countries, much more rapidly than the corresponding expertise. A trade in mining expertise has therefore developed alongside the coal trade proper. Germany relies on coal imports, but can export mining industry services and advanced mining equipment. Geological conditions in the Ruhr and Saar coalfields forced Germany to drive forward development of deep working for hard coal years ago. For 30 years now, Germany has been mining hard coal at depths of over 1,000 m, and excavation is now at depths up to 1,600 m. Deeper extraction and more extensive excavation posed new challenges for both miners and equipment. Intelligent logistics, modern roadway development methods and longwall mining with ploughs or shearers combined with optimised process coordination offered pioneering solutions - solutions to enable costeffective coal extraction in the long term without compromising safety. Countries such as Russia, the Ukraine, China and the Czech Republic, where extraction is now reaching similar depths, can now benefit from this experience: they do not need to go through the same process of trial and development, but can draw on Germany's findings and ultimately save on costs. Now, Germany is offering this knowledge and experience on the international market on a client- and deposit-specific basis to continue providing mining countries with safe and cost-effective coal mining solutions and secure the energy supply. The presentation gives a number of examples of how international mining companies have used expertise from Germany to better meet the challenges of deep mining.

Aug 1, 2013

By A. Adhikari, P. Tukkaraja, S. Jayaraman Sridharan

Shafts are critical components of the mine ventilation systems and contribute significantly to the mine ventilation pressure. Estimation of shaft pressure losses is an important aspect of mine ventilation planning and shaft frictional pressure losses are extensively studies. Shock losses contributed by shaft buntons are estimated using the interference factor model developed half a century ago. This study aims to develop a better performing prediction model for shaft buntons using state of the art experiment and numerical data, and machine learning techniques. Results show that the present prediction model is performing poorly, and the prediction performance can be improved by incorporating additional predictor variables. The Artificial Neural Network standardized Machine Learning model developed in this study is able to predict the shaft bunton shock loss with high accuracy (R2 = 0.956).

Jun 25, 2023

By T. B. Williams

THE British Columbia Coal Control was established in 1946 as a branch of the Department of Lands. Its functions are the administration of the Goal Act, the making of field and laboratory investigations bearing on the delineation and utilization of British Columbia coal deposits, and the dissemination of information concerning them. The Department of Lands in the Province of British Columbia retains and administers many of the Province's resources until such time as they are actively developed under the departments of Agriculture, of Forests, of Mines, etcc. The work of the Control is one of stock taking and appraising. We are picking up where the geological surveys leave off. In an effort to assist in the orderly, scientific development -of our excellent and extensive' ?Coat resources, we are bridging the gap between exploration and geological examination on the -one hand and mining on the other. All coal analyses required in the course of the investigations, together with? those requested by prospectors and others, are carried out in the very modern and efficient laboratories of the Coal, Petroleum, and Natural Gas Control. At its inception, the Coal Control began an investigation of coal seams in the Peace River area, specifically those contiguous to the Pine River valley about one hundred miles west of Dawson Creek. The occurrence of coal in the Peace River canyon, east of Hudson's Hope, bad been known since 1792, but the first record of production is for 1923.

Jan 1, 1951

By Stanko Nikolic

The Top Submerged Lance (TSL) technology, developed in the 1970s, is now widely used for the processing of a range of materials. TSL technology for continuous converting was first patented in the 1990s. The process is based on the use of calcium ferrite slag. Although this slag system had been applied elsewhere the phase equilibria had not been thoroughly investigated. This lead to a collaboration between the Process Technology group of Mount Isa Mines, now part of Glencore, and the Pyrometallurgy Innovation Centre (PYROSEARCH) at The University of Queensland. Through multiple research programs this complex system was successfully investigated. The results were then implemented within thermodynamic modelling tools. This combined new knowledge was then applied to the design and industrial implementation of the TSL continuous converting technology, ISACONVERT™. This paper describes the key findings of the research and how this was applied to the industrial implementation of the technology.