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By Ted H. Eyde

Improving the mineral industry's tarnished image describes in a nut- shell the reason why the Speakers Bureau of the Tucson Subsection of the AIME was formed. Let's go back in time about 3 years to the fall of 1971. Literally thousands of bills detrimental to the mineral industry were being introduced into Congress and State Legislatures. Unfortunately, many were being passed and signed into law. Clean air and water, zero pollution, preserve the environment, ecology, biodegradeable, wilderness were the words that the self- styled ecologists and environmentalists were preaching. The mineral industry either sat mute or in place of acting, reacted in a way certain to attract a maximum amount of bad publicity with a minimum amount of rhetoric. A mining company president, for example, commenting on the primary air standards in Arizona was reported by the press as having said, "we'll shut all the smelters down and put thousands of Arizonans out of work if we have to meet the Arizona standards." Or another defending a poorly planned highly visible open pit nonmetallics operation, "we'll take the whole mountain down if we want to, and nobody can stop us" and still another manager of Operations, "the bottom line is all that counts, to hell with all of this environmental nonsense."

Jan 1, 1975

By Yi Luo, Jian Yang, YUJIA LIAN

Scale physical models, constructed according to the principle of similarity theory, are widely used to simulate the mining disturbances to surrounding strata and to evaluate the effectiveness of implemented ground-control techniques. This technique has also been used for studying mining-induced surface and subsurface subsidence. The movements of the observation points installed on the physical model at different mining stages are currently measured using a total station, which is time consuming and inaccurate, especially on small-scale models.

By H. I. Meyer

The mine is a large open-pit copper mine located near Tucson, AZ. Mining operations involve shovels digging at relatively fixed locations and haul trucks moving the muck to a primary ore crusher, a primary waste crusher, and directly to waste dumps. The total investment in shovels and trucks is some $100 million. Fig. l is a schematic drawing of the operation. A static method of truck assignment is used; i.e., each driver is given one particular shovel to serve until reassigned by the dispatcher. A dynamic system is one where trucks are reassigned after each trip. The problem is to compute a near optimum assignment of trucks for efficient operation.

Jan 1, 1979

By E. Siami-Irdemoosa, S. R. Dindarloo

"Pareto analysis was used to investigate the failures database of a Hitachi EX1900 hydraulic shovel over one year of continuous operation. The hydraulic system and hydraulic links, hoses and piping were identified as the most critical system and subsystem, respectively. A three-parameter gamma distribution function was identified as the best fit for a probabilistic modeling of the time between failures (TBFs). This distribution was used in a Monte Carlo reliability analysis of the hydraulic system. Autoregressive integrated moving average (ARIMA), within the context of a time series analysis of the TBFs, was proposed as a viable alternative to the traditional technique of distribution fitting. The mean absolute percentage error (MAPE) metric was used to compare the two models. The MAPE value that resulted from the ARIMA was 66 percent smaller than that from the traditional technique in predicting the TBFs. Resumen ¦ Se usó análisis Pareto para investigar la base de datos de fallas de una pala hidráulica Hitachi EX1900 durante un periodo de un año de operación continua. Se identificó al sistema hidráulico y a los enlaces hidráulicos, mangueras y tuberías como el sistema y subsistema más importantes, respectivamente. Se identificó una función de distribución de tres parámetros gamma como el más apto para un modelado de probabilidades del tiempo transcurrido entre las fallas (Tabes por sus siglas en inglés). Esta distribución fue usada en un análisis de confiabilidad Monte Carlo para un sistema hidráulico. El promedio de movimiento integrado auto-regresivo (ARIMA por sus siglas en inglés), dentro del contexto de análisis de serie temporal de los TBFs, fue propuesto como una alternativa viable a la tradicional técnica de ajuste de distribución. Se usó el porcentaje de la media absoluta de error (MAPE) para comparar los dos modelos. El valor MAPE que resultó de la ARIMA fue 66 por ciento menor que el resultado obtenido con la técnica tradicional de predicción de TBFs."

Jan 1, 2015

By J. C. Draper

This subject was introduced last April in a paper presented in Birmingham, Alabama, by James E. Elkin, General Superintendent of Duquesne's Coal Department. This paper will cover some of the same data and in addition it will update and further describe our experience. Our Portal No. 3 was started in June 1965 with battery tractor-trailer face haulage. This mine is operating in the Sewickley seam in Dunkard Township, Greene County, in Southwestern Pennsylvania as shown on Fig. 1. The Warwick group of mines fronts on the Monongahela River and extends westward for some ten miles as shown on Fig. 2.

Jan 1, 1968

By Chee Theng

"Mining professionals are a resilient lot. Sure, copper prices are dismal, permitting processes seem interminable and the top mining companies are shedding jobs like a Shetland sheepdog sheds hair. All the more reason to hone technical skills, reconnect with old contacts and get one’s finger on the pulse of the industry.More than 400 did just that in the balmy sunshine and among the saguaro cactus of the Tucson venue of the SME Arizona Conference.Giving the keynote speech was Patrick Merrin, vice president at Hudbay Minerals (see box), while the luncheon speaker was University Distinguished Professor Mary Poulton, director of the Lowell Institute for Mineral Resources at The University of Arizona.“Attendance was great, especially given the copper price,” said Ta Li, vice president of business development at Tetra Tech and 2001 SME President. “The luncheon speaker was one of the better ones in recent years. Her talk contained a lot of fresh ideas, and practical versus theoretical concepts.”Talk about values, not economicsPraise was unanimous for Poulton, who gave a thought-provoking talk on “The New Face of Mining: The Culture Change for Compatible Mining.” Corporate social responsibility has been embraced by the metals mining industry, and it’s being done right, she said. “So why do we have more conflict? Why are there more protests? Why does permitting take longer and longer?” Poulton made a case for an approach based on compatible, rather than sustainable, mining to present a new face of mining that can be compatible with communities, cultures and the environment, and still be profitable. When the mining industry starts to talk about compatibility between what it is doing and what “me,” as the consumer, wants, what “we,” as citizens of a community, want, and what’s good for the “world,” we’re going to see the next culture change happen, she concluded."

Jan 1, 2015

By Peter Zhang, I. BERK TULU, Morgan M. Sears, Heather Dougherty, Ted Klemetti, DYKE MARK VAN, Gabriel S. Esterhuizen

Ground falls in longwall gateroad entries remain a concern in modern longwall operations. The gateroads are subject to changing horizontal and vertical ground stress induced by longwall extraction. These stress changes can result in failure of the strata around an entry leading to large deformations of the entry roof, floor and ribs. The gateroad support systems are required to control the failed strata while maintaining safe access to the longwall face and unimpeded ventilation. This paper presents research conducted to better understand the stability issues in gateroad excavations and to develop procedures for evaluating support and layout alternatives for longwall gateroads. Using the results of a field-monitoring program and numerical model analysis of case histories, a conceptual model of gateroad support needs was developed. The conceptual model formed the basis for developing a set of equations that can be used to estimate likely roof sag and support loading for given roof geology and longwall-induced loading conditions. The developed equations were used to compare predicted gateroad stability to field study results, showing satisfactory agreement. The calculation procedures are used to demonstrate their application in assessing support alternatives at a case study mine. It is concluded that the developed analysis procedures provide realistic assessments of likely ground stability and can be used to evaluate alternative gateroad support systems at operating longwall mines.

By A. W. Laughlin

Analytical costs are a major part of exploration programs in developing nations which may lack adequate laboratories. Laser-Induced Breakdown Spectroscopy (LIBS), a variant of atomic emission spectroscopy, can reduce exploration analytical costs and can provide the analytical results in <1 minute. CPI is now marketing battery-powered, backpack mounted analyzers, using LIBS to analyze for many elements of interest to the explorationist. LIBS is well suited to the analysis of elements in industrial minerals. Limits of detection in ppm for some of these are: Li-1, Be-2, Na-100, B-33, Sr-10, Ba-300, Cs-1, K-500, Fe-500, Mg-500, and Ti-500.

Jan 1, 1999

By Brianna Eiter, Max Barham, Tim Bauerle

While not well established, there is evidence that the mining industry is encumbered by several work-related fatigue risk factors. Compared to other industries, mine workers are more likely to report inadequate sleep and work longer hours per day. Given these observations, there is a critical need to identify effective ways to intervene, manage, and mitigate mine worker fatigue and sleepiness when present. One barrier to this is confusion around the similarities and differences between fatigue and sleepiness, which can result in these terms being treated as interchangeable regardless of context and make it difficult to assess and mitigate safety risk.

May 1, 2024

By B. S. Hulvey

Thin support liners are becoming more accepted and being developed with improved properties because the mining industry as a whole has been offering underground safe test trial sites. This is because of the huge potential for such products. Recent developments tend to indicate that the technology is “coming of age” and these are discussed in this paper.

Jan 1, 2003

By H. M. Park

Risk is a major factor in all mining activities, arising from many internal and external variables. The authors? research has resulted in a systematic method for the quantification of risk in mining projects (Park, 2012), and this research is being presented in a series of papers. The first paper (Park and Nelson, 2013a) identified the variables associated with risk in mining projects, and their effects and was published in the October issue of Mining Engineering magazine. The second (Park and Nelson, 2013b) discussed methods of assessing the overall risk associated with those variables (published at www.me.smenet.org), and presented a statistical model based on a survey of 31 experts. This paper will present an evaluation of the statistical model, using data from previous mining investment decisions in which the authors have been involved.

Oct 1, 2013

By Bruce Watzman

Can the United States mining industry achieve its long-stated goal of zero fatalities ? and what will it take to do so? Does it require new laws and regulations, as some propose, and a continuation of the commandand- control model that has been born out of more than 40 years of regulation and enforcement under the Federal Mine Safety and Health Act of 1969? Or, is it time to consider a new model to manage safety and health and drive continuous, sustained improvement? These are questions that many are debating as mine safety performance, while improved, appears mired in a trough where improvement followed by declines seems to have become the rule rather than the exception. Without doubt, U.S. mines have made significant progress in safety performance during the last four decades, yet the stalled decline in fatality numbers, the industry?s report card of its success or failure, has led some to question whether the industry will achieve zero fatalities in U.S. mining by relying solely on the Mine Act?s framework and implementing its regulations. These are questions the CEO-led task force, set up by the National Mining Association (NMA), considered as it sought to identify impediments to zero fatalities posed by the current regulatory regime. Out of that effort came CORESafety, a common safety and health framework that relies on a management system approach to improve safety and health performance. The goal of CORESafety is to achieve zero fatalities and a 50-percent reduction in the rate of injuries in U.S. mining within five years ? 0:50:5. CORESafety is built on the plan-do-checkact model, which has been successfully deployed by industries, mining and nonmining alike, to drive continuous improvement in safety and health performance. The improvements in safety performance that can be achieved by shifting from a command-and-control regulatory approach to a risk-based systems approach built on the plando- check-act model have been documented in numerous industries. For example, the United Kingdom quarrying industry (Fig. 1), not satisfied with the number of reportable accidents being experienced 1995-2000, established a hard target of a 50-percent reduction in the number of reportable accidents during the period 2001- 2005. Having met this target, the industry then established a further target zero for the period 2006-2010. The mechanism to achieve these reductions? The plan-do-check-act model.

Jan 1, 2014

By J. J. Moore

Combustion synthesis, or self-propagating high-temperature synthesis (SHS), reaction systems are discussed with respect to thermodynamics and kinetics. In particular, the effect of the process parameters, e.g. particle size, [All] ignition and combustion temperatures, on these self-sustaining reactions is discussed. Combustion theory is used to investigate the effect of the overall actuation energy of the SHS reaction on the combustion front propagation rate and in obtaining a clearer understanding of the transition from stable to unstable propagation. Finally, examples of the application of combustion synthesis to advanced materials processes are made, in particular the synthesis of Ni-Ti-X intermetallic shape memory alloys, TiC-AI2O3 and ZrB2-AI203 ceramic composite materials.

Jan 1, 1992

By J. R. Walls

The United States potash industry had its beginning in the early Colonial days. Potash was initially manufactured by leaching of hardwood ashes in large iron pots. Production of potash was recorded as early as 1631 in New Hampshire, and in Maine a few years later. According to the census of 1850, the production of potash was America&apos;s most thriving chemical industry and, at that time, 569 plants were reported producing potash from wood ashes. Interest in potash was so great prior to the 1800&apos;s that the very first United States patent, signed by George Washing- ton, was granted for the production of potash on July 31, 1790. A new era for the production of potash began when potash was discovered by the analysis from a brine well in 1839 near Stassfurt, Germany while exploring for salt. The predominant use of potash at that time was in the chemical industry rather than agriculture. The discovery, by Justice von Liebig in about 1858, that potash salt contributed greatly to the essential plant food in soil opened up an enormous potential market for a suitable potash material.

Jan 1, 1985

By Lynn B. Hales

The Supervisory Computer System at Cities Service copper mine and concentrator at Miami, Arizona was installed at Pinto Valley in the spring of 1975. Design and specification [l] of the digital system was initiated jointly by key plant personnel at Pinto Valley and staff of Cities Service Research and Development Company. The Pinto Valley digital system [2] may be classified as a supervisory control system of hierarchical design. There are three fully independent satellite computers which retrieve and reduce the raw plant data from each of the three main operating areas - the primary crushing plant, the fine crushing plant, and the grinding and flotation plant. While the three satellite computers are core resident systems, the master computer is a disc-based operating system which also interfaces with a computer controlled on-stream x-ray analyzer system. Figure 1 illustrates the basic system configuration [3]. The software systems required to support a large system are quite diverse and vary greatly in function. The philosophy followed in dividing the software into three categories was designed to: 1) fully utilize existing process knowledge of technical staff; 2) delegate certain software tasks to outside sources already skilled and trained in software development; and 3) maintain final control over the design and operation of each system.

Jan 1, 1976

By BARBOSA AMILTON, Denise C. R. Espinosa, David B. Dreisinger

Chelating resins can be used to recover important metals from different sources, and it is important to understand which resin is most suitable for each metal [1]. This review  benefits the mining industry because chelating resins can be used to recover metals from low-grade ores and mining tailings, increasing the industrial process efficiency [2–4]. Furthermore, the use of chelating resins in mining processes and mining tailings has the common problem of metals contamination, with iron being the main contaminant in low-grade ores and tailings. Understanding how contaminants decrease ion exchange efficiency is significant for industries [5

By Jorgen Elbrond

The calculation of open pit operations&apos; capacities has been the subject of many studies using computer simulations. The common problems of simulation are that if one desires a realistic picture of an operation the programming work becomes long and expensive and that the program requires a large computer and long time to run. The method presented in this paper overcomes these problems by using a straightforward calculation procedure. It is based on the queuing theory&apos;s simple formula for waiting time in a closed circuit and uses a system of correction factors, which reflect the loading, travel, and dumping times&apos; relative variabilities and which have been found by 1) mathematical analysis and 2) simulations of basic circuits. The method includes the main parameters of the operation: numbers, sizes and operational availabilities of trucks, shovels and dumping point, distribution of the production over shovels, trucks&apos; loading, travel (loaded and empty) and dumping times as well as their variabilities, shift&apos;s composition. The procedure models: the average duration of a complete truck cycle during stationary and non-stationary periods during the shift as a function of the number of trucks in the circuit, the composition of the average 100% operated shift, the simultaneous probabilities of operationally available shovels and trucks and the distribution of shovels and trucks according to production and cycle times. The procedure can be programmed for a small computer and requires only short computing time, which makes extensive studies of various parameter combinations practical to carry out. The development of the method is an extension of previous work by Morgan and Peterson {1}, who by simulation established the relation between the match factor (which is the ratio between the sum of one loading time pr truck in the circuit and the complete net cycle time) and the shovel&apos;s efficiency, and by Hayes, Splaine and Whitaker {2}, who established this relation from a large number of observations in the Nchanga pit in Zambia. The present method establishes this relation by a straightforward calculation procedure. Theoretical solutions to some situations are found in the litterature on the queuing theory. The papers {3},{4} and {5} give solutions to situations, which fall outside those encountered in the shovel-trucks circuit. These solutions together with simulations of in-termediary situations have been used to establish an interpolation procedure for the correction factors to be applied to the waiting time formula in order to cover the situations encountered in practice.

Jan 1, 1977

By Richard L. Bullock

Drilling of small diameter blast holes in the conventional tunnel driving system or mining operation still consumes a significant part of the time and money required to extend an opening in rock. The use of pneumatic drills for most small hole applications has been the dominant tool used by miners and tunnel men alike throughout the world. But now, a, trend has been started that is showing major inroads into the traditional areas of pneumatics drilling for all types of rocks. Operators dealing in very soft materials, such as coal, salt or potash, traditionally had the option to use hydraulic power for their drilling tools. Twelve to fifteen years ago, drillers in medium hard, but nonabrasive rock extended their drill machine option by helping to develop a drill that still used air to power the hammers, but relied on hydraulic power for the rotational torque and feed thrust. (1) This was a significant step forward, particularly for those who drilled in rocks that were compatible to rotary-percussion bits. However, this application was in fact somewhat limited to the limestone and dolomite formation of mid-United States and the softer sediments in Europe. Now high performance rock drills have been developed, using all-hydraulics for both the hammer and rotation, that have many advantages over the conventional pneumatic systems. In two previous papers on this subject, (2)(3) this author reviewed in detail: 1) the characteristics of each of the manufacturer&apos;s products that were on the market; 2) The specific advantages of the all-hydraulic drilling systems; 3) Data from the applications of these drilling systems that was in use; 4) What was needed to further develop this drilling system and utilize its potential in the mining or tunnelling cycle. This paper will attempt to update previous papers, without reiterating many details of drill descriptions or

Jan 1, 1976

By C. Garcia, A. Potulska, J. J. Opazo, T. Comi

"The Sierra Gorda SCM sulfide ore processing plant began commissioning in the third quarter of 2014. Located in the Atacama Desert in northern Chile, the project is an open pit mine and Copper-Molybdenum processing plant is one of the most highly-instrumented operations in the world. It is the first hard rock operation in Chile and the second in South America to utilize HPGR technology. It is a significant Molybdenum resource especially in the first five years and the Molybdenum separation plant is complex. Designed to process up to 60 million lbs. of fine Molybdenum per year, it uses the latest technology and equipment to ensure superior recovery and product quality. It also has gas handling and alarm systems to fulfil the Company’s vision of “Zero Harm”. This paper discusses the overall operation and issues relating to the concentrator start-up. These include a review of the mineral processing design, the unified process control center and management information systems, and the correlation of geological and metallurgical performance data (mine-to-mill) for use in anticipating and preparing for treatment of diverse ore deliveries. INTRODUCTION Sierra Gorda SCM is a joint venture partnership with KGHM International (owned by KGHM SA, Poland), Sumitomo Metal Mining, and Sumitomo Corporation (Japan) operating in northern Chile. The Sierra Gorda open pit mine and Copper-Molybdenum processing plant will become one of the largest mines in the world. The need for optimum production efficiency and sustainability has driven the creation of the most modern, well-instrumented mine in Chile. This paper contains a general review of the project including geology and history. This was a very fast-track project going from greenfield site acquisition to mill start-up in 10 years. Highly-experienced and motivated engineers and technical staff have overcome many significant challenges resulting in a rapid ramp-up of production capacity. A potential expansion to double the production rate in the fourth year of operation has also been intensely studied. The Sierra Gorda property is located in the Atacama Desert of northern Chile, in the District of Sierra Gorda, Region II of Antofagasta, Chile (see Figure 1). There is almost no precipitation in this area. The mine site is generally flat with some rolling hills. The project is located about 5 km from the village of Sierra Gorda at an elevation of approximately 1,700 m above mean sea level. The village is near a highway and railway line. The city of Calama, home of the famous Chuquicamata Mine, is located about 60 km northeast of Sierra Gorda. In addition, the SG mine is in the midst of numerous other mines including Spence, Esperanza, Mantos Blancos, El Tesoro, Lomas Bayas, Gabriela Mistral, El Abra, Radomiro Tomic, and Escondida, to name a few."

Jan 1, 2015

By G. H. Schnakenberg

In 1986, the US Bureau of Mines (USBM) embarked on a major research effort to develop technology that could substantially reduce worker exposure to face hazards by simply relocating the equipment operators to an area of relative safety. This reduced-exposure mining system (REMS) research effort enhances the USBM&apos;s ongoing health and safety efforts aimed at reducing and controlling dust and noise and reducing accidents through training and better mining practices. This paper reports on the progress made on the developing research and demonstrates the technologies required for the computer-assisted teleremote operation of continuous mining machines, haulage systems and roof bolting machines.

Jan 1, 1997