Search Documents

Maximizing margins in competitive markets demands superior productivity. Unfortunately, management systems developed early this century for other industries often drive counterproductive behaviors choking mining productivity. Many executives and managers waste valuable time and effort relying on simply training and communicating to improve managerial practices and attitudes. In covering practical human behaviour, the paper explains why this fails -and explains how to use systems to successfully drive improved managerial practices and attitudes. It highlights use of modern performance Measurement, Analysis and Reporting systems to drive behaviors and improve margins -without capital investment -and make executive and managerial work easier and more effective.

Jan 1, 1999

By P. C. Fletcher, E. Kaya

The Bond grindability testing procedure has been standardized to measure the same grindability values, i.e. Bond work index (BWi), for the same ore when tests are performed in different laboratories or by different operators. This is accomplished by the standardization of mill dimensions, tumbling speed, grinding ball charge weight and distribution, sample ore charge weight in the mill and operating practice. The results of this investigation reveal that the Bond work index grindability values may differ substantially with different standard Bond ball mills. This paper will review the results.

Jan 1, 2002

By D. S. Brown

Few issues pose quite as profound consequences to the quality of life and the creation and distribution of wealth as how we protect the natural environment. No longer a peripheral but a global concern, the environment, once almost nobody's business, has now become everybody's business. It is also the single biggest issue facing mining and mineral activities. This heightened ecological awareness and sensitivity have spawned a new commitment to restore, protect, and preserve nature. But that very commitment poses difficult socio-economic trade-offs, such as: What and how many resources can be given up to prevent and reduce pollution? What are the opportunity costs associated with meeting higher environmental standards? What problems are more important or pressing than others and should be given priority? Choices have to be made that may entail unintended consequences for other societal goals.

Jan 1, 1994

By A. J. Kwitowski

Remote control is usually associated with deep mine, continuous mining machines. This is because thin-seam operation precludes an onboard operator's compartment or the mine has approval to conduct extended cut mining. Using a tethered or radio-linked control box, the remote operator is typically situated 3 to 15 m (10 to 50 ft) from the working face. The operator receives direct operational cues through senses like vision, hearing and feel. Remote control is sometimes touted as a safety feature. However, this is not always true, as operators are not provided protection from roof and rib falls or being crushed between the machine and a rib. Remote control operators are also left exposed to dust and noise. Teleoperation described here is the computer-based, distant control of mining machinery from a protected operator compartment located out of the line-of-sight from the operational site. Video, sound and other sensory information are gathered through sensors and electronically transmitted to and displayed at the operator's location. The teleoperator responds to the information and makes decisions that are initiated by control devices (usually switches). These control commands are then electronically transmitted to the re¬mote machinery and the appropriate machine function(s) are carried out. Teleoperation increases the safety of mining machine operators as it removes them from the immediate vicinity of hazards. The US Bureau of Mines' involvement with teleoperation dates back to 1979. Following feasibility studies, a highwall milling system (HMS) was developed and tested. A deep, thin-seam, room-and-pillar system (TSRPS) has been designed and is currently being surface tested.

Jan 1, 1992

By N. Niemuth

Strong demand for copper in developing nations such as China and India, plus the additional demand for industrial minerals to supply the Arizona construction market, brought about a record-setting year for the state?s mining industry. The value of Arizona?s copper production set a new high of $5.5 billion and pushed the total value of mineral production to $7.58 billion. This was also a record. As it has for many years, Arizona ranked first in nonfuel mineral production in the U.S. In addition to leading the nation in copper, Arizona ranked in the top five in molybdenum, sand and gravel, gemstones, perlite, silver, zeolites and pumice. Generally strong and rising prices, especially toward year?s end, fostered a bullish atmosphere that encouraged significant levels of acquisition and exploration. This activity has spread beyond the normal commodities to include some, such as manganese and fluorspar, that have not been mined in Arizona for decades.

Jan 1, 2008

By Tad S. Golosinski, R. Larry Grayson

Online education is not new. During the last decade, it has reached the stage where many universities offer a variety of courses, degrees and programs without any associated residency requirements. The most successful of the online universities, University of Phoenix, offers hundreds of accredited programs for close to 100,000 students throughout the world (www.phoenix.edu). Online education is considered to be a valid equivalent to traditional, classroom-based education. It is best suited to the needs of mature students with full-time jobs and a desire to deepen their knowledge. While most of the e-business has experienced severe setbacks during the last two years, e-education shows no signs of slowing down. On the contrary, the number of students and institutions offering online education keeps growing. The value of e-education associated expenditures was expected to reach $300 billion in 2001 (Sanoff,2001), making it a serious and mature industry.

Jan 1, 2002

By Peter W. Lipman

Structural and topographic relief in the Sangre de Cristo Mountains of northern New Mexico provides a remarkable cross section through the recently recognized 23-26 m.y.-old Questa caldera and cogenetic volcanic and plutonic rocks. Although largely eroded, remnants of an ash-flow sheet of silicic-alkalic rhyolite and associated more mafic lavas of the Latir volcanic field are preserved as far as 45 km beyond the source caldera. Within the caldera, the tuff ponded to a thickness of 2-3 km and enclosed chaotic megabreccia fragments which slumped from the caldera walls. At the time of ash-flow eruption, the volcanic field was severely deformed along northwest-trending faults related to the Miocene Rio Grande rift, with most intense deformation occurring within the caldera. Strata were steeply tilted and locally overturned along presumably listric faults. Ash- flow tuffs locally underwent secondary flowage over concurrently developing fault scarps and accumulated within structural basins as rheoignimbritic lava flows. Cogenetic batholithic granitic rocks, exposed over an area of 20 x 35 km, range from mesozonal quartz monzonite to epizonal porphyritic granite and aplite, with the shallower and more silicic phases most abundant within the caldera. Compositionally and texturally distinct granitic phases define a highly evolved resurgent intrusion within the caldera, an incomplete ring dike along its southern margin, and a large mass of less fractionated quartz monzonite south of the caldera. A negative Bouguer gravity anomaly is closely confined to the area of ex- posed granitic rocks; it also reflects boundaries of the Questa caldera. The gravity anomaly is interpreted as defining the extent of the underlying batholith, emplaced into lower parts of the volcanic sequence and underlying Precambrian rocks. Paleomagnetic determinations indicate that the granitic rocks were above Curie temperatures at the time of caldera formation and regional listric faulting, yet most are little different in radiometric age from the intensely deformed volcanic rocks. These relations indicate that the batholithic complex represents the source magma body for the volcanic rocks, into which the Questa caldera collapsed, and was largely liquid at the time of regional tectonic disruption. Compositions of the volcanic and plutonic phases changed from early calc-alkaline metaluminous rocks, to weakly peralkaline silicic rhyolite and equivalent afredsonite-acmite granite at the time of the caldera formation, then back to post- caldera calc-riebeckite granitic rocks. Maximum concentrations of alkalis and minor elements such as Rb, Th, U, Nb, Zr, and Y were reached at the time the caldera formed about 25-26 m.y. ago, but the major molybdenum mineralization of the Questa district took place when the late calc-alkaline granitic ring intrusions were emplaced about 23 m.y. ago, along the south margin of the caldera.

Jan 1, 2013

By Lim Thi Duong, Du Duy Bui, Thuat Ngoc Pham, Chuc Ngoc Pham, Que Anh Nguyen, Hoa Anh Bui, Chi Thi Ha Nguyen, Hoan Thanh Nguyen, Bac Quang Nguyen, Kien Trung Nguyen, Dung Trung Doan, Nhiem Ngoc Dao

The microstructures and kinetics of a rich iron ore ( TFe = 65.84%) of Na Rua mine, Vietnam, used for the iron production were investigated in this study. Thermal behaviors of iron ores were well-examined by heating microscopy, thermogravimetric analysis, and differential thermal analysis. After being pelletized and then oxidatively fired at 500–1200 °C for 2 h, the pellets fired at 1200 °C (P1200) displayed a hard and dense structure with a decent compressive strength of 317.9 kg/pellet whereas those fired at 500 °C (P500) had a soft and spongy structure. The reduction of iron pellets conducted in a flow of a 60–100% CO2/ Ar gas mixture at 900–1100 °C showed significantly higher efficiency than the reduction using coal. The spongy pellets showed superior performance for the reduction in the CO/Ar gas mixture compared to the dense ones, compatible with the production of sponge iron. When mixed with an amount of coal, P1200 designed for iron production in the blast furnace demonstrated an impressive reduction activity compared to P500 and previous studies. The kinetics of pellet reduction was determined by the diffusion of substances through the solid product layers having the mathematical model of 1 − 2 3 f − (1 − f )2∕3 = kt . The microstructures of pellets during the oxidative firing and reduction were also examined by X-ray diffractometry; scanning electronic microscopy; energy-dispersive X-ray spectroscopy; and Brunauer, Emmet, and Teller method.

Jun 7, 2022

By A. Nieto

This article is a review of previous discussions about underground mining method selection and classification with the purpose to clearly define and classify the two groups of variables (indicators) involved in the mining selection process: key deposit indicators (KDIs) and key mining method indicators (KMIs). This paper provides a simple and clear approach for the classification and selection of a feasible underground mining method based on a predetermined set of favorable deposit characteristics, which are defined as key deposit indictors (KDIs). This article also gives a summary of the key advantages and disadvantages associated with every underground mining method based on their key mining indicators (KMIs). The selection method given in this paper is based on defining field KDIs and comparing them to the KDIs that are favorable to every considered mining method. By cross validating a matrix of favorable KDIs, the paper presents a simple approach to rank several underground mining methods using a scale from favorable to less favorable accordingly to the ore deposit characteristics (KDIs). KMIs are used to further complement KDI rankings by analyzing every method’s KMI performance based on the expected productivity of the mining operation being considered. To further assist the reader through the selection process, this paper gives basic sketches representing each of the primary underground mining methods discussed in this paper. Each method is given using the same 3D isometric view as spatial reference to assist the reader with visual interpretation and comparison between methods.

Jan 1, 2010

Despite the current economic downturn that is now decimating iron ore production, Minnesota?s mining operators remain optimistic about the long-term prospects for the industry. Reflecting this optimism, the development of several new mining projects continues in the state. The future of mining in Minnesota was the featured topic at the combined 82nd Annual Minnesota Section of SME Meeting and 70th Annual University of Minnesota Mining Symposium. More than 500 mining industry professionals, including engineers, executives, mining managers and equipment suppliers from the around the world, attended the meeting, which was held April 14 and 15, 2009, in Duluth, MN. The combined meeting featured a keynote session with three distinguished speakers plus a panel discussion by representatives from several of Minnesota?s taconite producers. The keynote speakers were Curtis Clark, president and chief operating officer, Behr Dolbear, who gave a presentation on the ?State of the Mining Industry.? Phil Newman, chief operating officer, CRU Strategies, spoke about challenges facing the mining industry and James A. Skurla, acting director, Bureau of Business and Economic Research, Labovitz School of Business and Economics, University of Minnesota Duluth, discussed the importance of mining to northeastern Minnesota?s economy. The taconite producers panel discussion included Jonathan Holmes, vice president and operations manager, ArcelorMittal; Ed Latendresse, vice president and general manger, Hibbing Taconite; John Tuomi, vice president operations services, United Taconite and Mike Mliner, vice president and general manager, Northshore Mining. The mangers provided updates on their respective operation The meeting included concurrent technical papers sessions on mining, processing, environmental and nonferrous mining. The sessions included technical papers that provided information on the status of a number of new mining projects in the state. The conference also offered a SME short course titled ?The basics of iron mining.? A tradeshow that featured about 100 companies and organizations offering products and services to Minnesota?s mining industry ran in conjunction to the conference. It was estimated that more than 900 people, including conference registrants and special invited guests of the vendors, attended the tradeshow opening reception. This was the largest trade show in many years. The Minnesota Section of SME also held its annual business meeting during the conference.

Jan 1, 2009

By R. Zunich, E. Rybinski, M. Grondin, B. Flintoff

It is uncommon these days to read a business magazine or newspaper without finding a reference to Knowledge Management (KM), and its critical importance to corporate success. One definition of KM is: “getting the right knowledge to the right people at the right time and helping them to put information into action in such ways that strive to improve organizational performance.” In the minerals processing industry we could assert that we have been practicing this for years through effective operator training. In most cases we would probably be wrong. Training has certainly filled the need of addressing safety and basic operational issues, but we must collectively focus on education (learning), and the difference, as measured in outcomes, is not at all subtle. This paper briefly examines the history of training and education in the mining industry, and looks in more detail at the impact of one company’s approach to empower its workforce, while keeping the ultimate goal clearly in mind: “The great end of knowledge is not knowledge, but action.” (T.H. Huxley)

Jan 1, 2001

By B. Schimm

Mining of material without blasting and / or selectively becomes more and more important for high quality ROM-products. Surface Miners have been developed especially for this purpose. The cutting technology of these machines has been improved, so that harder material as well as wet and sticky materials can be cut with better results now. Especially the cutting drum design and more precise drum manufacturing process now allow production and equal tool wear over a long period. The better knowledge of rock parameters influencing the cuttability and cutting results allow higher production, less cutting tool wear and therefore reduced production costs.

Jan 1, 1999

By J. K. Wilmshurst

Absorption, emission and reflection techniques for the study of [molten] inorganic materials at high temperatures have been critically examined. In general, the reflection technique is the most satisfactory for tine study of pure materials, while the absorption, and possibly also the emission techniques, may be useful for studies of certain dilute solutions. In the present investigation infrared emission spectra for sodium nitrate and silver chloride were obtained together with absorption spectra derived from reflectivity data by the method of Robinson and Price for sodium nitrate, silver chloride, lithium and potassium fluoride and their 1:2, 1:1 and 2:1 mixtures and for solutions of zirconium tetrafluoride in lithium-potassium fluoride (1:1) and sodium-potassium fluoride (1:1). It is concluded that vibrational spectroscopy cannot give unambiguous information concerning the existence of complex ions in fused salt, mixtures.

Jan 1, 1963

By L. F. Ruppert, P. A. Freeman, R. C. Milici, S. J. Tewalt, L. J. Bragg

The U.S. Geological Survey has completed a dig-ital coal resource assessment of six of the top-producing coal beds and coal zones in the northern and central Appalachian Basin coal regions. These include the Pennsylvanian-aged Pittsburgh, Upper Freeport, Lower Kittanning, Fire Clay, Pond Creek, and Pocahontas No. 3 coal beds and coal zones. Resources were calculated on all of the coalbeds/zones, with the exception of the Lower Kittanning coal bed. Preliminary original resources are estimated at about 93 billion short tons (84 billion tonnes), of which about 66 billion short tons (60billion tonnes) remain. Much of the remaining coal in all five coal beds/zones is thinner [<3.5 ft (1.07m)] and deeper [>1,000 ft (305 m)] than the coal that has been mined, but economic resources are still available and mining in each coal bed/zones will continue throughout this decade and into the next given current market conditions.

Jan 1, 2001

By Wallace N. Thomas

The present interest in large diameter grinding mills and the rapidly rising cost of the drive in proportion to the cost of the mill establishes a need to explore the drive system in detail. The drive for a seven to eight thousand horsepower mill will cost from 1350 thousand to $600 thousand which represents nearly half the total cost of the mill package, and requires as much building space as the mill proper. Some of the drive components require a longer time to manufacture and the installation time and costs are equal to those for the mill. It is apparent that the drive has become a dominant factor in the overall mill design consideration. A new plant requires a tremendous investment in both time and money. With the high degree of competition in the mining industry, low capital cost is an exceedingly important factor in the development of a project. It is just as important, however, to insure that the equipment is going to perform satisfactorily for the anticipated life of the project without adding unplanned operating, maintenance and replacement costs. This is the position in which the engineer or designer usually finds himself and is really one of his primary functions -- establishing a realistic compromise between cost and performance.

Jan 1, 1969

By Grover Wallace

At is important for today?s mining executives and leaders not to underestimate the fact that, while the recent downturn in the economy did take its toll on balance sheets and productivity, factors such as emerging countries, aging workforces, globalization and individual knowledge growth did not lay dormant while the economy was in a lull. It is key for mining leaders to be proactive in their talent strategies. Successful mining companies are developing a clear, concise and communicated strategy and placing a high priority on recruiting the right talent in global markets that parallels their business strategy. They are focused on placing the right people in the right jobs.

Jan 1, 2011

By P. I. James, M. R. Baker

Este artículo analiza la nueva producción de cobre a partir de "minerales de desecho" de baja ley usando la tecnología de Blue Planet Strategies DEMET™ (Dynamic Electrode Mining Effluent Treatment, por sus siglas en inglés), que tiene como objetivo salvar la brecha de procesamiento entre la solución débil de lixiviación en operaciones de extracción por solventes/electrowinning (SX/EW), removiendo electroquímicamente los metales a partir de corrientes débiles y a la vez generando productos concentrados en metales objetivo en un análogo funcional de extracción por solventes (SX). Se estudió el tratamiento de la débil solución de lixiviación pregnant (PLS por sus siglas en inglés) y se usó para estimar los impactos económicos y de producción para una hipotética lixiviación en pilas de cobre brownfield y una operación aumentada DEMET usando SX/EW para tratar el "mineral de desecho." Se presenta la remoción de cobre a un 86% de eficiencia en las placas por debajo de 0,1 g/L de cobre con un consumo de energía de 0.55 kWh/lb de cobre y una concentración del producto mayor a 10 g Cu/L. El modelamiento arrojó aproximadamente $2/ lb para la producción total de cobre y costos de tratamiento menores o iguales a $1/lb con un inmediato aumento del margen bruto de operación del 12% para el brownfield incrementado. Se indicó también un aumento de la vida de la mina con un margen bruto promedio de 38% en la producción aumentada de "mineral de desecho" con valores de cobre de $3.25/lb.

Jan 1, 2014

By J. O. Stephens

During the late 1940&apos;s and early 1950?s, the Westinghouse Combustion Turbine Division built and demonstrated a residual oil-burning locomotive on six eastern railroads. Plans were made to convert to burning pulverized coal, and a single combustor was operated at a full-pressure condition in the laboratory for about two years. During the mid-1960&apos;s to mid-1970&apos;s, there was considerable interest in coal-burning MHD and a combustor was developed which would also be applicable to combustion turbines. In the early 19801s, the BCR National Laboratory (BCRNL) became affiliated with the University of Pittsburgh, and a program was begun, supported by the Stare of Pennsylvania, to develop an all-purpose combustor for use with industrial and utility boilers and eventually with combustion turbines. In this paper, we review the work of almost 40 years, indicate our present position, and propose steps to be taken leading to efficient and environmentally acceptable power generation from coal, and specifically to coal-burning locomotives.

Jan 1, 1986

By Earl C. Herkenhoff

Editor&apos;s note: The subject of mining on the moon can generate a wide range of strongly held opinion, from those leaning toward the view that, ultimately, such activity is the destiny of mankind to those who believe that all suggestions for moon mining to date are unrealistic, wildly expensive and in the hands of people who &apos;know nothing.&apos; MINING ENGINEERING herewith publishes some of the basic pros and cons on the subject of moon mining by writers who are among those holding strong views on the subject, with the hope that some of our readers may be interested in joining this debate. Every mineralogist and most mineral industry people were keenly interested in the examinations of the first moon rocks brought back by US astronauts in 1969. Suffice to say that the examinations revealed nothing exotic in the mineral makeup of the very limited rock samples. The rocks were generally of igneous type, dark-colored and contained some common, Earth-type minerals. There was, in Earth terms, above average TiO2 content, but they contained nothing of commercial significance by Earth standards. Therefore, interest in moon minerals rapidly faded. Years later, on Sunday, May 4, 1986, living in Reno, NV, this author was shocked to read a local newspaper article by the Dean of the Mackay School of Mines, University of Nevada, Reno, headlined, "Moon Mining Not Far Off." Considering that the announcement more or less coincided with a slump in our domestic mining industry, the immediate questions in a reader&apos;s mind

Jan 1, 1991

By F. G. Crack, R. V. Ramani, R. L. Frantz

Management for mine construction and development differs from that needed for routine mine production and maintenance. An integrated approach to managing mine development projects must consider contract documents; management organization of a project; the project manager&apos;s role and the field supervisor&apos;s responsibility; and the use of scientific techniques for planning, scheduling, executing, and controlling projects. Professional project management encompasses the following: • Preparing contract documents that establish technical and financial schedules, and detail the responsibility for the physical work commitment. • Developing a project&apos;s organizational structure, to clearly define the roles of the project manager and the field supervisors. • Establishing project management and field supervisor relationships, to avoid ambiguity in assigning responsibility and to ensure desired project progress. • Using management science techniques, particularly networking techniques such as the critical path method for planning scheduling, executing, and controlling projects. Project Versus Production Management Project management differs from routine production management in the following ways: • Uniqueness: A project is unique. Production operations tend to be repetitive. The magnitude of one-time capital expenditures for many facets of mine development warrant special skills and attention. These professional project development skills must already be available by prior experience in the management team. • Personnel: In projects, personnel are usually assigned on a specialty basis and frequently change with the project activity. On the other hand, production personnel work together, more or less permanently. • Management Structure: In a project there may be several staff-line relationships that are not clearly defined and change with changing project activities. In a production situation, the lines of communication and authority are usually well defined. • Time Frame: A difference between project and routine production management is that project activities have comparatively less well defined durations and often tend to be relatively short-term. Production usually has both long-term and short-term plans and well defined long-term and shor-term goals. In project management, formal, critical, short-term reviews are frequently required. In production management, five year plans can be formally adjusted quarterly and annually. Short-term weekly or daily reviews can be informal. • Response to Delays: Delays in a development project may occur without anyone being immediately aware of their existence or suspecting the magnitude of consequence. In contrast, any delays in the production process can be easily identified from prior results comparison. Additionally, the response is quick, usually in a set routine. This can be traced back to the management structure and personnel. • Control Techniques: Measurements of project progress for control are not easily made due to the variety of activities that are carried on at the same time by different work groups. The yard-sticks of performance measurement for individual activities, let alone for the total project, are not easily established. However, due to the difficulty in detecting project delays, a workable control system is vitally important to a project manager. To apply a scientific project control technique such as "management by exception" requires specific planning and monitoring from the project manager for each activity in the project. Production and productivity are quick and effective yard-sticks of measuring performance in a routine operation. Control techniques required in production management usually revolve around these measures. Construction Contracts The construction contract is an important document that establishes contract scope, technical and financial details of the work, and achievement deadlines. It may also serve as the contract document to pay for work done and to verify field progress with planned progress. In practice, it is a good idea to develop a job-specific contract. This whole area is replete with legal precedence and procedures, and it is not the intent here to deal with the intricacies of establishing a contract document. But it is necessary to have an understanding of major contract types. Construction contracts are extremely important legal documents. They may vary in work specifications and enforcement of the provisions. Due to their nature, they must be composed with legal help and will take some time to compile. Even with all the precautions and provisions, it is not uncommon to find owner and contractor disagreeing. Therefore, it is important to include a way to resolve any difference quickly and to incorporate aspects of the contract as part of an overall management control tool for efficient project management.

Jan 7, 1982