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By Jeffrey C. Wynn

Since the early 1970's, the U.S. Geological Survey (USGS) has carried out exploration geophysical research on non-basemetal strategic mineral commodities, including uranium, lithium, gold, potash, and chromite. The chromite study (largely completed) and the potash study (still going on) carried out during the past 4 years have not been aimed at the discovery of new ore reserves, but instead were designed to complement exploration by private mining companies. The USGS has carried out research not normally conducted by these companies, but which can be used by them in their efforts to increase production of strategic minerals. Results of the chromite and potash studies highlight the importance of: 1) a laboratory-research phase (petrophysical and petrographic studies) at the beginning of work on any new commodity; 2) an operative or functional ore-deposition model to serve as a conceptual framework, and the necessity to continually test, refine, and modify it during the study; 3) indirect geologic/geochemical indicators, secondary associations, and the use of multiple physical properties; and 4) the use of a systematic inverse-cost sequential-exploration (i.e. lowest resolution and lowest cost first) strategy to keen the exploration economically reasonable. The keystone to the success of the study is frequent and substantive dialogue among geologists, geophysicists, and geochemists.

Jan 1, 1981

By Christopher J. Bise

Traditionally, mine drainage systems have not received the high level of emphasis on careful engineering design which has been rendered to many of the other auxillary operations. This may be due, in part, to the situation-response approach toward dealing with an influx of water. When the installed system becomes inadequate, costly alterations to the pump, such as staging or speed increases, are considered expedient solutions. In order to rectify this situation, computer-aided solutions to mine drainage problems could represent an efficient alternative to the methods presently used. This paper will consider the application of microcomputer technology to mine drainage problems and will show how the relative economy and convenience of microcomputers can make them become valuable analytic tools at any mine site.

Jan 1, 1983

The ventilation of a mine is one of the key elements to a successful mining operation. It is, or should be, one of the primary concerns of the mining engineer at an underground mine. Too frequently, however, insufficient thought is given to future requirements. As a result, the mines suddenly find themselves with ventilation problems that cannot be corrected economically, or in short order, and have to suffer the consequences of being on the verge of having units shut down from time to time until the venlilaltion system can be improved. Insufficient ventilation in capital-intensive mining can cause production losses, the values of which far outweigh the significant costs of providing and operating an adequate ventilation plan. Many theories, and techniques in planning and control of underground ventilation systems have been developed over the years . It is the intent of this paper to point out some of the fundamental concepts, from the practical point of view, in the design and operation of a ventilation system, with special reference to underground mines using a room-and-pillar method.

Jan 1, 1986

By P. L. Sibrell

Previous research by the U.S. Bureau of Mines showed that autoclave cyanide leaching of used automobile exhaust catalysts for recovery of platinum group metals (PGM) was technically feasible. This work involves a more detailed investigation of the chemistry of the dissolution of PGM in cyanide solutions. The PGM species in solution identified by ultraviolet spectroscopy. Pt and Pd cyanide complexes were square were The planar in geometry, while the Rh complex was octahedral. The rate of dissolution of the PGM was also investigated using a rotating disk technique. Dissolution rates increased in the order of Rh, pt, and Pd, respectively.

Jan 1, 1994

By W. Dan Hausel

In previous reports by Hausel et. al., (1979 a, b, and c), Leighton and McCallum (1979), and McCallum (1974;1979), several exploration procedures were examined as to their effectiveness in locating kimberlite intrusives in northern Colorado and southeastern Wyoming, where approximately 90 kimberlites have been recognized within 5 districts (Figure I). Briefly, geological mapping and stream sediment sampling for indic- ative heavy minerals of kimberlite (pyrope garnet, chrome diopside, and magnesian ilmenite) proved to be the two most effective methods in isolating kimberlite occurrences within the granitic terrain of Colorado and Wyoming (Hausel et. al., 1979 a, b, and c; Leighton and McCallum, 1979). Where a kimberlite intrusive is deeply weathered, remote sensing using color and color infrared aerial photography may be a potential reconnaissance tool in kimberlite exploration. The kimberlitic eluvium supports thicker grassy vegetation, and at least one species of grass (the Bluebunch Wheatgrass) is found to grow only within the eluvium. The result is that vegetation in the kimberlitic eluvium is a better infrared reflector than the vegetation in the surrounding granitic soils (Hausel et. al., 1979 b; McCallum, 1974

Jan 1, 1980

By S. R. Dismuke

Ore at the Magmont Mine in southeast Missouri is extracted by the room and pillar method on two and sometimes three horizons. In 1991, an innovative plan was formulated for recovery of high grade ore in pillars using cable bolts to accommodate spans of more than 27 m (90 ft). A test area was subsequently selected and a recovery plan developed. A cooperative rock mechanics study effort by COMINCO METALS, the U.S. Bureau of Mines and the University of Utah was later established. When initially opened in 1968, the planned production rate was about 1,000,000 tons per year. Due to declining reserves, the production rate was decreased to 630,000 tons per year in November 1992. Pillar recovery now accounts for approximately 40%-50% of the mined tonnage and plays a vital role in allowing Magmont to continue to operate.

Apr 13, 2011

By K. C. Watts

The Silver City mining region is located in Grant County, southwestern New Mexico (Fig. 1). This area is well known, having produced large tonnages of base and lesser amounts of precious metals over the past several years. Mining within the region continues today, as well as exploration activity, which seems to have been on the increase since the recent discovery of a large skarn-associated Zn-Pb-Cu replacement deposit near Pinos Altos, a mineral district within the region (McKnight and Fellows, 1978). Because the Silver City area contains a number of mineral districts and retains promise for additional deposits, as suggested by widespread hydrothermal alteration and favorable igneous rocks, it was selected as the focus of two independent geochemical studies, both seeking to enhance anomaly-to- background contrast in order to improve our abilities to detect blind metal deposits or subtle manifestations of near-surface occurrences. The first of these independent studies involved the systematic sampling of those secondary Fe-Mn oxides that occur within coatings, selvages, and fault fillings, and then the selective extraction of these oxides from the host-rock matrix by chemical methods. The second study sought to isolate clastic Fe-Mn-rich materials from the heavy fraction of stream alluvium. The ultimate source of the clastic Fe-Mn oxides is presumed to be the same coatings, selvages, and fault fillings sought by the direct sampling of joints, but has been transported as a result of lateral erosional processes.

Jan 1, 1981

By Peter C. Ashbrook

The Regional Copper-Nickel Study was initiated in large part because of fears that copper-nickel development might cause adverse effects on the environment from air pollutants such as sulfur dioxide (SOZ) emissions from a smelter, and water pollutants such as acid mine drainage. The Study comprehensively examined the potential for ad- verse effects on the environment and possible mitigation measures on both a local and regional scale by first characterizing existing air and water quality, and existing sources of pollution, and then developing hypothetical development scenarios to model potential adverse effects. This paper gives a brief overview of the Study's findings concerning air and water resources.

Jan 1, 1980

By A. Masutomi

Although great strides have been made during the past two decades in the reduction of the severity of accidents and injuries in underground coal mining, the number of accidents resulting in disabling injuries and lost time has continued to increase. Looking ahead to the 1990s, the reduction of accidents and incidents typically found in these latter categories should be emphasized in safety training for underground coal mining. Loss control is an approach which shows promise for applications in mine safety training since loss-control strategies focus on the pre-contact stages of an incident rather than on the incident, itself. Applied to safety training, the heightened awareness of personnel to workplace hazards at the pre-contact stages should result in a reduction of accidents and injuries. This paper explains the concept of loss control and shows how it can be applied in the development of the needs assessment for miner training programs. An example, based on research conducted at the continuous-miner worksite, is provided.

Jan 1, 1991

By S. C. Suboleski

Forecasts indicate that the acid rain bill currently before Congress is likely to cause an increase in demand of 30 to 40 million tons per year of compliance quality coal from Central Appalachia. This represents a doubling of this segment of the coal business. This paper will examine how this doubling can be met, what the likely implications for pricing are, the major uncertainties associated with these predictions, and the likely outcomes of the growth in compliance coal. Finally, some implications for fuel planners will be discussed.

Jan 1, 1993

By E. Karampinos, P. Morissette

"INTRODUCTION Ground support is a critical element in maintaining the stability of mining drives in deep and high stress mines. In challenging ground conditions, it is necessary to continuously explore ground support strategies that can control the resulting large deformations. It is an objective of mining operations to optimize the ground support by selecting both appropriate systems and the time of installation of each reinforcement element. A successful ground support strategy will result in the use of a system that ensures both the structural and operational integrity of the excavations and mitigates the need for rehabilitation. Preliminary ground support design is often based on empirical observations and methods. Once a design is implemented, field trials, observations and in situ pull tests are used to fine tune or improve the design. Although not often employed during this process, numerical modelling can provide helpful insights on the impact of different ground support strategies. In this respect, it is possible to explore the use of multiple options before selecting the most promising ground support system for implementation in field trials. The challenges associated with the numerical modelling of rock support for mines have been described by Lorig and Varona (2013) and Potvin (2017). The employed numerical models should capture all potential failure modes of reinforcement over the mining sequence of the excavation. In particular, it is important to emulate the observed in situ ground support performance, as well as the influence of the installation sequence of the support. However, the time and expertise required for this type of modelling of ground support is not often available at mine sites. Even when the expertise is available it requires a major time and commitment of resources to set up, run and calibrate the sophisticated models capable of explicitly capturing the behavior of ground support. Rock reinforcement is an integral part of all ground support systems used in underground mines. Long flexible tendons can reinforce the rock mass deeper into the walls and create a thicker reinforced shell around the underground excavation. This paper focuses on the optimization of the cable bolting strategy in squeezing conditions at the LaRonde Mine by integrating the 3D distinct element method (DEM) in the design process. A calibrated numerical model is used to investigate a series of cable bolt configurations and provide recommendations for the ground support design."

Jan 1, 2018

By Kalman N. Isaacs

Aerial photography is a recognized and integral part of the search for petroleum and for the metallic ores, but its application lags seriously; in the search for the industrial minerals This is, in all probability, a result of the relatively stringent economics of the various industrial mineral industries. The oil and mining companies (particularly the oil companies) can afford generous exploration budgets and thus can experiment with unorthodox approaches such as photogeology. The industrial mineral industry is more restricted, and up to now has relied on less sophisticated methods of exploration. The industrial minerals have been generally defined as those materials extracted from the earth that are neither metals, metallic ores, fuels, nor ground water. Any group chat must be defined in such a negative manner, by citing the things that they do not include, must in themselves be extremely diverse in character. This is truly the case for the industrial minerals; the full list of industrial minerals is incredibly long and tends to increase year by year.

Jan 1, 1964

By T. S. Govindan

The first step in energy conservation in any industrial plant involves implementing many of the day-to-day "house-keeping" items such as fixing leaks, turning out lights, etc. When this step has been accomplished, additional opportunities require a detailed analysis of the energy systems, evaluation of risks and costs, and assignment of priorities. Examples of conservation schemes drawn from the experience of Du pont's Energy Management Consulting Services will be discussed. The utility of heat balances for kilns and dryers in minerals processing will be outlined. The inputs needed from Management for the success of conservation efforts will be discussed.

Jan 1, 1978

This United States Bureau of Mines study is based on a review of U.S. mine fire accidents that occurred from 1970 through 1989. Information on these accidents was obtained through investigative reports written by Mine Safety and Health Administration personnel. For this study, 260 mine fire accident reports were examined. A previous Bureau research effort established that fires causing fatalities were more likely to occur in haulage entries than at any other underground location. This study has found that the most prolific source of haulage entry fires was the inadvertent grounding of trolley wires. The largest segment (15 out of 40 trolley wire fires) resulted from not maintaining adequate clearance between the trolley wire and the vehicle. Several novel fire prevention and control ideas have evolved in response to frequently occurring fire-related problems. These included; discriminating power isolation devices, wire cutting devices, more accessible fire extinguishers, vehicle overcurrent protection, and vehicle fire suppression.

Jan 1, 1994

By J. R. Johanson

In recent years the procedures for functionally designing bulk storage bins and hoppers have evolved from qualitative guess and try methods to a quantative method based on theory and tests of the bulk solid to be stored. This quantative method, developed and implemented by Dr.'s A. W. Jenike and J. R. Johanson as with any new design, must prove its effectiveness and validity in the actual operation of the finished equipment. How accurate are the theoretical predictions? Is it possible to extrapolate from bench size tests on a small ample of the bulk solid to the full scale bin design? Can the theoretical designs be economically translated into working hardware? In this paper the answers to these questions are discussed in light of actual bin operations.

Jan 1, 1968

By Richard M. Tinlin

The mining industry needs to assure compliance with the Federal Water Pollution Control Act Amendments of 1972 (Public Law 92-500). Congress has enacted this legislation with the intent of preventing, reducing, and eliminating pollution of the nation' s surface and groundwaters. Recognized sources of pollution such as seepage from tailings ponds, waste dumps, and contaminated effluent from mine dewatering operations pose a serious threat to adjacent groundwaters. In addition, technological innovations being implemented by the industry such as in situ leaching of low grade ore deposits may also lead to ground- water contamination. An adequate monitoring methodology designed to meet the needs of the mining industry is needed. Monitoring and control methodology devised for other man- caused sources of ground- water pollution - e. g., landfills - offer considerable promise for adaptation to the problem. The prediction of deleterious effects on groundwater quality usually requires extensive geohydrological data in addition to a thorough analysis of the mining activity that is underway or projected. If the avail- able data are adequate, mathematical models of surface and groundwater flow can be constructed that will help to predict effects on water quality. Data are inadequate to allow a realistic interpretation of pollution potentials. These data can be supplemented by computer simulation as a method to explore a number of possible environmental effects and also to develop a minimum-cost approach to identifying and gathering the additional necessary supporting data. Incorrect assessment of the important environmental considerations may, in many instances, prove to be the weakest link in analyzing the financial feasibility of a mining operation.

Jan 1, 1973

The floatability of a bituminous coal in NaG solutions was evaluated using a modified Hallimond tube to delineate the role of the electrostatic interaction between bubbles and particles in determining the coal hydrophobicity. Zeta potential measurements showed that bubbles are negatively charged in the entire pH range tested, while coal particles are positively charged below pH 6.0 and negatively charged above it. Also, both sodium and chloride ions were confirmed to act as indifferent ions without any specific effects for both coal particles and bubbles. Flotation as a function of pH exhibited a maximum and minimum at low salt concentrations which is shown to be determined mainly by the coal hydrophobicity as measured by a new hydrophobic levitation technique. At high salt concentrations (above 0.1 mole/dm3), the flotation without such maximum or minimum is controlled by the electrostatic interaction between the bubble and the particle.

Jan 1, 1992

By D. R. Nagaraj

There are few organic ligands that can adsorb effectively on noble metals, especially gold, in aqueous media. Ligands containing sulfur and nitrogen donors are known to be the most effective. Dithiophosphorous acids, for example, are known to adsorb on gold under certain conditions and these, along with xanthates, are used traditionally to recover gold values by flotation from ores. These compounds, however, are not necessarily selective for gold since most of the associated sulfide minerals are also floated. Monothiophosphorous acids, on the other hand, were recently discovered to float gold values selectively from sulfide-containing ores in a mildly alkaline medium; thus the dicresyl monothiophosphate is now used commercially in a gold flotation operation in the U.S.

Jan 1, 1991

By D. A. Fenton

The reliability of large diameter, high horsepower ball mill is paramount when large production and minimum downtime is required. The 17 ft. x 56 ft. double compartment ball mill at St. Lawrence Cement Company has the first gearless drive built in North America and has the world's largest hydrodynamic bearings currently built and running. The machine has seen three years operation and has met its specifications. The mill was designed by Aerofall Mills Limited and the gearless drive built and designed by the Canadian General Electric Company. This paper discusses the operation of the first North American installation of a gearless drive ball mill from the mechanical, electrical and process aspects.

Jan 1, 1977

By Andrew J. Neale, Chelvan Veloo

P.T. Freeport Indonesia currently operate a 600,000 t/d mining and 125,000 t/d milling operation in the remote highlands of Irian Jaya, Indonesia. The isolated location and generally difficult working conditions make for challenges not encountered in most North American operations. In spite of this, the mill technical groups have been able to develop and maintain a highly effective level of plant wide automation. This has been achieved through the appropriate selection of available technologies and the implementation of innovative management practices. This paper provides an overview of the control systems currently installed and focuses on those practices which have resulted in the long term success of process control at Freeport.

Jan 1, 1997