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By Robert E. Lovett

The truly educated man is better prepared to meet the challenge of the times. This challenge can be either beneficial or harmful depending upon one s orientation, Certainly man can no longer continue in the way of his father or even in the manner of his own previous experience as he seeks self-fulfillment, unless he is willing to sacrifice inner integrity--unless he is willing to compromise self-determination and self-expression. He must make a choice as society moves rapidly into high gear in the areas of automation and cybernetics. Industry, a unit of society, has a high stake in meeting this challenge, The better prepared and more mature its personnel, the better the end result as it attempts to meet the challenge. It therefore has a vital concern in proper training of such personnel, that their contribution will be of maximum quality. The specialized training required demands a broad liberal arts background which gives the individual a wider perspective upon which to base judgment. This greatly aids his development as he enters graduate school or goes directly into industry. In either case, his value to industry is enhanced. It would seem that the small liberal arts college provides the best environment for such a program, Consideration of several factors will, I hope, throw some light on the severity of the problem.

Jan 1, 1966

By Clarence A. Johnson

The discovery of the Prudhoe Bay field temporarily reduced interest in the development of coal conversion processes, but interest is being re¬newed by the current energy crisis. According to M.A. Wright, Chairman of the Board of Humble Oil and Refining Company(l), the reserve in the Prudhoe Bay bield has been confirmed to be about 10 billion barrels. At first glance this appears to be an extremely large reserve which will eliminate supply problems for the United States for some time. This feeling of security is lost when one realizes that by 1980 the world will consume the reserves of a Prudhoe Bay or a Libya, or Venezuela in less than a year, based on the recent predictions of U.S. and world reserves made by Eastman-Dillon, Union Securities Company(2). Recent forecasts of U.S. demand and source of supply made by Kenneth E. Hill of Eastman-Dillon are shown in Figure 1. This forecast shows a decline in domestic supplies (excluding Alaska) after 1973, with the total domestic supply leveling off in 1975 at about 13 million barrels per day. Since the predicted demand increases from about 14 million barrels per day in 1970 to about 20 million barrels per day in 1980, about 35% of domestic consumption must come from imports or non-conventional sources by 1980. More imminent is the shortage of low sulfur fuel oil which has been created by the new, tough air pollution regulations that are basically legis¬lating eastern coals out of the market. As an alternate to importing large quantities of low sulfur fuel oil or importing and desulfurizing regular fuel oil, one of two domestic solutions is possible: stack gas clean-up or solids fuel pretreatment. Stack gas clean-up may be the cheapest approach for old installations, but fuel pretreatment has real advantages for new installations. Coal pretreatment at the mine could eliminate all solids fuel handling

Jan 1, 1972

By Earl G. Hoover

For most geologists and miners the term "asbestos" refers to a group of highly fibrous silicate minerals that readily separate into long, thin, strong fibers of sufficient flexibility to be woven, are heat resistant and chemically inert, and possess a high electric insulation and therefore are suitable for? uses where incombustible, nonconductive or chemically resistant material is required. The United States Mining Enforcement and Safety Administration (MESA) specifically refers to the naturally occurring minerals chrysotile. amosite, crocidolite, termolite asbestos, anthophyllite asbestos, and actinolite asbestos as "asbestos" if the individual crystal fragments have the following dimensions; length -greater than 5 micrometers, maximum diameter -less than 5 micrometers, and a length to diameter ratio of 3 or greater. Since asbestos has been identified as one of the ten most carcinogenic substances (a cancer causing agent) it has become, for many government regulatory agencies, a major issue concerning banning emissions to the environment.

Jan 1, 1978

By I. H. Douglas

All grade control methods in use currently by the mining industry are imprecise. The methods suffer from being locally inaccurate, leading to are loss and contact dilution. An ore/waste indicator variable can be used to predict the probability of ore occurrence at a given location, Po. Then, an ore grade Zo for an ore location and a waste grade Zw for a waste location are obtained. The expected revenue is calculated at each location, based on its probability of being are or waste, the corresponding grade, and on the cost of mining and processing the ore or the waste. Finally, the decision of whether to recover the block is based on the expected revenue value for that block. The method is illustrated with an example taken from the Jerritt Canyon district in northeastern Nevada.

Jan 1, 1994

By G. R. Doubek

Dual Tube Reverse Circulation (DTRC) drilling has been extensively used for collecting groundwater information for the dewatering program at Amax Gold Inc. Sleeper Mine. This paper presents a discuss ion of the types of data which can be collected from DTRC drilling, as well as the effect submergence has on the data. A simple low-cost method of injection testing has been developed using DTRC equipment, allowing quantitative data to be obtained from exploration or test holes. Potential yields can be determined for each drill location, allowing siting and design of production wells to be optimized.

Jan 1, 1992

By Robert L. Major

The expanded role which coal has been assigned in the energy future of the United States has raised numerous policy questions. The very complexity of these questions makes them suitable to analysis by econometric models. However, as the Wall Street Journal indicated in its recent article, business' success with such models have been mixed. I have been asked to present my views as to how coal producers can use such models and in what ways the industry is likely to be impacted by such models. I do not presume to speak for the whole coal industry, but only to share with you the personal observations of one who has worked "both sides of the street", having been employed' both by government and a consulting firm prior to joining the coal industry. In my opinion, the use of econometric models to analyze the coal industry will impact the coal producers in two main ways. First, their use by government will have a profound impact on future government policies related to the mining, transportation and utilization of coal. Second, such models, when properly calibrated and refined, may become useful tools for the coal producers in doing market research and long-range planning. While the former has already begun to impact on the operating environment or the coal industry, the latter is still in the embryo stage.

Jan 1, 1977

By J. E. Lema

America's bulk commodity transportation systems have taken on a new look in the 1970's and 1980's. Railroad systems, barge lines providing inland and intra- coastal waterway transportation, and Great Lakes carriers have undergone substantial changes through mergers and acquisitions, consolidations of ownership and control, and construction of modern intermodal transportation facilities linking railroads and water carriers. The new look has generated some concerns and opportunities with regard to producers and shippers of bulk commodities which are characterized by the necessity of moving large quantities of heavy materials long distances. Clearly such transportation requirements call for efficient railroad and water carrier services. Shippers of commodities like coal, grain, .chemicals, minerals, ores, forest products, petroleum products, and heavy manufactured goods find reductions in transportation competition lead to concerns that rates charged by carriers will not be sufficiently constrained by market forces. At the same time, new policies on contracting for railroad services can lead to greater efficiencies, a rewarding opportunity for carriers which should be shared with shippers and consumers of bulk commodities. Then, of course, there's a related problem that in the absence of effective competition, the benefits of increased carrier efficiency will not be passed on, in part, to shippers and consumers, causing losses in markets for producers.

Jan 1, 1986

By F. Robert Hollo

Programmable controllers have achieved remarkable acceptance over the relatively few years since their introduction. They provide some unique advantages over conventional relay and solid-state logic, which they often replace. Programmable controllers are discussed in both conceptual and functional terms, followed by an exploration of their applicability to material handling tasks with particular emphasis on conveyor systems.

Jan 1, 1973

By RALPH BALTES, AMIR EHSAN KIANFAR, FABIAN UTH, ELISABETH CLAUSEN

As indoor positioning provides particular challenges due to the unavailability of GPS signals, various systems such as ultrawideband (UWB), radio frequency identification (RFID), ultrasound, and wireless local area network (WLAN) have been proposed in recent years. Some of these technologies are currently being marketed and some are still being developed. UWB technology allows for higher precision while also reducing power consumption. Hence, the underground automation and localization systems can use this technology for more accuracy and robustness. This article discusses new robust UWB modules used for underground positioning and collision avoidance with regard to human safety in underground mining operations.

Jul 31, 2020

By Cristian Saavedra, Patricio Zarate

Flotation collectors play a crucial role in mineral flotation by selectively adhering to mineral surfaces and aiding in their separation from gangue material. They are heteropolar molecules, as defined by Sutherland and Wark (1955), featuring non-polar hydrocarbon chains and polar groups interacting with mineral surfaces to induce hydrophobicity selectively. The importance of collectors in mineral processing, as underscored by Lotter and Bradshaw (2010), lies in their ability to enhance recovery rates and improve selectivity, thereby optimizing the extraction of valuable minerals from complex ores. Collectors are classified based on their mechanism of action, as proposed by Laskowski (2010). This classification categorizes collectors into three groups: water-soluble compounds, water-insoluble “oily” collectors, and water-insoluble amphipathic compounds forming molecular films at the water/gas interface. This complements the chemical structure-based classification by Sutherland and Wark (1955) and Suoninen and Laajalehto (1993), offering a comprehensive understanding of collector diversity in flotation systems. Collector selection is an iterative process crucial for optimizing mineral processing efficiency, as emphasized by Lotter and Bradshaw (2010). Understanding the significance of collector mixing or synergy outcomes is paramount for enhancing mineral flotation efficiency and sustainability. Taguta, O’Connor, and McFadzean (2018) demonstrate that mixed collector systems enhance interaction enthalpies and microflotation recoveries, indicating improved performance. McFadzean, Castelyn, and O’Connor (2012), along with Critchley and Riaz (1991), delve into investigating synergistic interactions between collectors, offering insights for strategic selection. Observations from the study of collector synergy, as noted by Wakamatsu et al. (1980), reveal nuanced relationships surpassing individual collector behaviors. The methodology outlined in this paper provides valuable guidance for classifying and selecting collectors based on specific application needs, while also suggesting the potential for synergistically improving recovery across fine, intermediate, and coarse particles.

Feb 1, 2025

By Rahul Bhaduri

Mercury levels in Twin Creeks Vista pit ore (previously Chimney Creek, North pit ore) increased substantially since plant start-up in November 1987. Consequently, modifications were necessary to minimize industrial hygiene hazards and potential operational problems. The original plant design included mercury control measures. With progressive increases in mercury levels, the issue had to be re-addressed. Modifications to operational practice, industrial hygiene and management philosophy will be discussed. Additionally, a detailed examination of the mercury vapor suppression system currently employed at Twin Creeks will be presented.

Jan 1, 1994

By M. Ramokhothoane, S. Rupprecht

"NTRODUCTION Women employment in the mining industry dates back to the 19th century. Various parts of the world, for example, India, Japan, the United Kingdom and the United States of America had women employed in large numbers. The women’s jobs were primarily manual in nature. Women were used to carry coal in buckets from the coal face and out the mine, and those who worked on the surface plants were used to sort waste rock from the coal product. Other heavy industries, which were traditionally male dominated, for example the military, also had a considerable number of women supporting the war effort. The outbreak of war also caused a shortage of labour, which in turn, necessitated that women were used in various roles during the war. After World War II, women returned to their traditional roles, but had acquired new skills, and had a different outlook to life. The wearing of pants and short hair became fashionable, as a result of being in the army.Various laws were passed which prevented the employment of women underground. Different countries had rules that they believed were in the best interest of women and were of the opinion that the rules somehow were protecting women against the harsh working conditions. In South Africa, post 1994, there has been a shift in thinking in regard to the employment of women in the mines. WOMEN IN SOUTH AFRICA MINING In the words of the Minister of Women in the Presidency, Minister Susan Shabangu, “women must take centre [sic] stage as the country gears itself for the implementation of radical socio-economic transformation policies and programmes in the next five years” (SA Government News Agency, 2014). In as much as some progress has been made in advancing women, more needs to be done in order to realize sustainable benefits in the economy. The emancipation of women is a reality and remains top of the South African government agenda. From the Authors’ experience there are two types of men in the mines. The first group support change and see the value in it. To them, women in mining bring in the diversity and play the complementary role in achieving greatness. There is no fear of job security and humiliation but a great sense of “camaraderie”. The other group continues to enforce stereotypes, which works against the spirit of redressing the imbalances of the past."

Jan 1, 2018

By R. Hildebrandt, K. Cybulski, G. V. Goodman, Z. Dyduch, M. L. Harris, M. J. Sapko

Past research showed that bituminous coal dust remains dry and dispersible in the presence of moisture. Rock dust must disperse with the coal dust to effectively inert a propagating coal dust explosion. Non-treated rock dust readily absorbs moisture, limiting its dispersibility, while anti-caking treated rock dusts can remain dry. The National Institute for Occupational Safety and Health contracted the Central Mining Institute in Poland to conduct large-scale testing in their Experimental Mine Barbara to determine if a treated rock dust can be as effective as non-treated rock dust in attenuating or quenching coal dust explosions under the same experimental conditions. INTRODUCTION One of the goals of the National Institute for Occupational Safety and Health (NIOSH) is to conduct research to reduce the risk of mine disasters and provide workplace solutions to reduce the risks associated with accumulations of combustible and explosible materials; the most common form of which is the generation of coal dust during the mining process and its subsequent distribution downwind. Dispersible rock dust is a primary defense for preventing coal dust explosion propagation in underground coal mines, and its properties are defined in 30 CFR 75.2. “Pulverized limestone, dolomite, gypsum, anhydrite, shale, adobe, or other inert material, preferably light colored, 100 percent of which will pass through a sieve having 20 meshes per linear inch and 70 percent or more of which will pass through a sieve having 200 meshes per linear inch; the particles of which when wetted and dried will not cohere to form a cake which will not be dispersed into separate particles by a light blast of air; and which does not contain more than 5 percent combustible matter or more than a total of 4 percent free and combined silica (SiO2), or, where the Secretary finds that such silica concentrations are not available, which does not contain more than 5 percent of free and combined silica.” An earlier NIOSH investigation of rock dust revealed two significant concerns with the supply of rock dust to U.S. coal mines: 1) insufficient particles <200 mesh (75 μm) and 2) all rock dusts when wetted and dried formed cakes and were not easily dispersed with a light blast of air (1). Past research by the U.S. Bureau of Mines and others showed that bituminous coal dust remains dry and dispersible in the presence of moisture (2). Rock dust must also be dispersible in concert with the coal dust to effectively inert a propagating coal dust explosion (3, 4, 5, 6). Non-treated rock dust, however, readily absorbs moisture, limiting its dispersibility, while a rock dust treated with long-chain fatty acids (such as stearic acid) can remain dry and dispersible. Stearin-treated rock dust has been used in British coal mines (7) and is commonly used in Polish coal mines.

Jan 1, 2019

By Gerald W. Cormick

In a complex society such as ours, the range of "negotiating" relationships is constantly increasing. These negotiating relationships have emerged as a direct result of the diffusion of power or influence to new sectors and emerging concerns. Even within organizations, the myth of the authority-based heirarchical structure has given way to the reality of constant negotiations between superior and subordinate and with peers in the organizational structure. In the broader context, the corporate organization finds it necessary to reckon and often negotiate with organized employees, suppliers, buyers, government agencies and a range of organized private interests ranging from minority groups to environmental organizations. In response to this diffusion of power and the conflicts which it has engendered, a variety of conflict avoidance, conflict managing or conflict resolution techniques has developed. The purpose of this paper is to attempt to differentiate between some of the conflict intervention approaches which have appeared "on the market", and to suggest three bases for selecting among them: 1. The "role" of the conflict intervenor; 2. How far the conflict has developed; and 3. The breadth and impact of the issues involved.

Jan 1, 1979

By Brij M. Moudgil

Florida produced more than eighty percent of domestic phosphate during 1974. This amounted to more than thirty-five million short tons. Ninety percent of this production was used in the production of fertilizers. Other uses of phosphate include food preservatives, fabric dyes, optical glass, photographic films, soaps, plastics, pharmaceuticals and animal feed ingredients. Marketable phosphate rock projections for the nest decade forecast a very healthy growth for the Florida phosphate industry. Associated with the expansion, however, are the corresponding problems of water conservation, air and water pollution and land reclamation. Recognizing mining as an interim land use, the industry is presently engaged in a very active reclamation program. The proximity of the central Florida deposits to rapidly developing urban areas makes it important to undertake successful and well planned reclamation programs. Water use and conservation is of vitil importance to the industry. Water withdrawal from existing aquifers and discharges into drainage systems are closely regulated by state agencies. Water is stored and recycled to maximize usage. In some instances water is even returned to major aquifers through a series of recharge or connector wells. The phosphate industry has spent over 200 million dollars in the past decade for research, development and implementation of pollution abatement and water conservation systems.1 The following discussion outlines various phases of phosphate mining in central Florida today, with emphasis on research in waste disposal techniques and progressive land reclamation programs.

Jan 1, 1975

By W. F. Visser

The growing availability of information and data analysis capabilities provides new opportunities for improving the performance of operations. By using real-time measurements and artificial intelligence, it is possible to respond faster to changing conditions, while accurate and timely information permits the rapid evaluation of changes and fast business improvement decisions. This paper presents a blueprint for system alignment, organizational design and management practices to leverage these developments in performance-driven operations management in mining and mineral processing.

By H. C. Siebert

According to the "Survey of Energy Resources 1980" (1)*, which was prepared by the Federal Institute for Geosciences and Raw Materials in Hannover (FRG)for the World Energy Conference 1980 in Munich, the world coal deposits are assessed at 775 billion tce proven reserves 448 billion tce of them recoverable and 6 161 billion tce additional resources. If one ignores growth rates, the current world coal output of 2,8 billion tpy gives our recoverable reserves a static life expectancy of 175 years. With an average increase in world output of 3,2 % like between 1973 and 1980 this range would be further shortened to an alarming degree. Furthermore, the criteria used to distinguish between workable and unworkable resources give rise to the suspicion that deposit characteristics are not always taken into account to a sufficient degree. For example, little attention is paid to major ?Bonitaet" - factors such as dip and seam thickness. There have been wide-ranging scientific discussions on the lower limit for workable coal resources, but no such limits have been set at the other end of the scale. Otherwise it is well known that performance and costs are badly affected den in level and moderately inclined seams the seam thickness is more than 4 to 5 m, because special mining methods have to be used beyond this limit. These are associated with significantly higher costs than with the winning of seams of ?normal? thickness.

Jan 1, 1985

By W. Ellison

Worldwide development of commercial markets for FGD (flue gas desulfurization) gypsum is described and used as a basis for assessing potential overall market growth and regional demand foreseen in the U.S. during the 1990s. Diverse strategies are outlined for cost-effective substitution of this major supply from acid rain control retrofits (power plant scrubbers) for natural gypsum in the principal, existing markets: gypsum board and portland cement. Another focus of utilization forecasting is a key group of related. new-product advancements including floor screeds, mining mortars and various types of innovative construction products.

Jan 1, 1993

By J. M. Marek

The determination of the proper cutoff grade for an open pit metal mine is based on economic criteria and the operating philosophy of the mining company. Previous papers have dealt with the balance of a fixed mine production capacity versus economic return. Mine production capacity is often controlled by the amount of mining equipment and the working area in the pit. A complete cutoff grade strategy is a balance of economic return of mining higher grade material versus the capital costs of additional production capacity and the operating cost of moving the waste and low grade material to assure proper ore release. An approach to the problem is presented which is based in part on work by previous authors and provides guidelines to proper cutoff grade strategy encompassing the time value of money and variable commodity prices.

Jan 1, 1985

By E. Bonates

Dispatching systems have attracted considerable attention in the last years due to substantial gains in productivity achieved through their implementation. These systems will be extensively used in the future by mine operators as a means of optimizing productivity. This paper describes a computer simulation model designed to study the feasibility of continuously dispatching trucks in open-pit mines based on different operating procedures. The system developed is semi-automated and performs an active role by suggesting to the dispatcher the best assignment according to each specific circumstance. It is modeled based on an advance-clock increment to reduce computing time and allows the insertion of heuristic dispatching policies and equipment real-locations when breakdowns occur. Dispatching procedures taking into account long-term production objectives are considered in system development.

Jan 1, 1988