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By J. R. Sturgul

A dynamic input-output model for a coal power enterprise that now includes four underground coal mines, three coal washing plants, a power plant and a railway transportation system was developed. The model is applied to analyze investment alternatives for long-term development, including the expansion of existing mines, the opening of new mines, the construction of new coal washing and power plants and the upgrading of the railway system. As a result, the optimal investment strategy with capital schedules and projected sector outputs is obtained. Also, the importance of the new power plant to the strategic development of the company is demonstrated. It is concluded that, without applying a dynamic input-output model, it would be much more difficult or impossible to conduct such a systematic and compete analysis.

Jan 1, 1999

By Mark Gershon

This paper describes a linear programming (LP) application that schedules mining operations in an optimal manner. The model is developed such that it can be applied to a broad spectrum of mining activities. While linear programming has been applied to mine scheduling in the past, the models have been either site-specific or they have only optimized one aspect of mine operations without regard to others. The Mine Scheduling Optimization (MSO) concept makes use of a mathematical model to: (1) Determine the optimal operation of a mine, from mine to plant to market. (2) Account for mine-plant-market interfaces. (3) Optimize operations over the life of the mine. (4) Accomplish long, intermediate, and short range planning.

Jan 1, 1982

By Eric Jackson

The presentation describes the operation and field test results of a seafloor massive sulphide prospecting system. The prospecting system is deployed from a work-class ROV, and it features a new and innovative electromagnetic ocean floor conductivity sensor. It also includes magnetometers, a multibeam sonar, and subsea cameras. The prospecting system has been used in two exploration campaigns - one in the territorial waters of Papua New Guinea (PNG) in 2007 and again in 2008 in both PNG and Tonga waters. The 2007 campaign used the prototype sensor, and the 2008 campaign used a Mark II version. Correlations between drill core samples and EM conductivity results are excellent. New prospecting system data will be used to help plan future core drilling locations. The presentation discusses the principle of operation of the EM conductivity sensor, discusses improvements made in the EM sensor and the overall prospecting system, and shows exploration results. Keywords: seafloor massive sulphide, geophysics, ocean floor, subsea, electromagnetic, conductivity, magnetometer, multibeam, core drilling

Jan 1, 2008

By Julian Boldy

The discovery of the Delbridge massive sulfide deposit in the Noranda district of Quebec resulted from an appreciation of the significance of a mercury leakage haloas a lithochemical pathfinder to blind ore, coupled to its location relative to a geologically inferred ore-bearing horizon within complex volcanic stratigraphy. Systematic sampling of microfractures present in outcrops delineated a diagnostic anomaly, drawing attention to an area considered prospective for buried ore. The massive sulfide deposit was subsequently found to be blind and topped at the 107-m (350-ft) level. This case history is presented in the context of its time and was the first volcanogenic ore deposit to be discovered utilizing mercury as a pathfinder in the Canadian Precambrian. The case history also illustrates that the practical application of an innovative technique coupled to a new geological interpretation can result in success, even on a property that was centrally located in a mining district and had undergone intensive exploration efforts over a 38-year period.

Jan 1, 1991

By Mark C. Williams, Thomas P. Meloy

Particle shape characterization is a complex task made more difficult because of the human eye's sophisticated recognition of shapes, giving rise to the assumption that shape analysis is considered a simple problem. Further exacerbating the problem is the question of whether particles have a general shape. Old and new shape measuring techniques are discussed, particularly the new image analysis methods techniques such as Fourier, Haar, Walsh and Delta. Problems with the current image analysis equipment and future research equipment needs are presented.

Jan 1, 1989

By Terry I. Mudder, Michael M. Botz

Discharge regulations for mine waters require relatively low concentrations for cyanide and metals, and the trend is for discharge limits to be lowered. In the event conventional treatment practices are not sufficient to meet discharge limitations, advanced treatment technologies such as ion exchange and reverse osmosis may be considered. Though these technologies will provide discharge quality waters, they also require the disposal of a concentrated brine and are relatively complex and costly to operate. Many mine sites currently using activated carbon in precious metals recovery present the opportunity to economically operate an activated carbon water treatment plant for polishing of effluents. This paper presents summaries of six ( 6) mining operations which have evaluated or use activated carbon for treatment of water and which also use carbon in precious metals recovery processes.

Jan 1, 1997

By Jerry Kolstad

The Stillwater Mining Company Base Metals Refinery (BMR) leaches a PGM bearing nickel/copper smelter matte to produce a concentrated platinum/palladium filtercake. The BMR employs a two-stage sulfate based leaching process. The first stage (nickel atmospheric leach circuit) leach is performed under atmospheric conditions at elevated temperature to leach the majority of the nickel present in the matte feed. Approximately 85% of the solids mass fed to first stage leach report to the second stage (pressure leach circuit) leach. The pressure leach circuit consists of two batch autoclaves in parallel. Each autoclave has a separate feed tank. This paper will describe the second stage leaching process and report associated operating costs.

Jan 1, 2000

By Barry J. Hansen

Mining can make two major contributions to the cleanup of the environment. The first of these is the extractive technology that has become highly developed as a result of centuries of development. Of equal impor­tance are the methodology of analysis and the development of engineering solutions that are the stock in trade of the mining industry. Despite the differences between the industries, the processes for the development of a mine and the cleanup of a hazardous waste site are similar. The characteristics that impact the ability to develop a suitable process for treating an ore body or correct­ing an environmental problem are those relat­ed to the distribution of the contaminant or metal in the host material.

Jan 1, 1991

By L. Evrard, M. Van Camp, J. Y. Yen, R. G. Reddy, D. Mantha

Viscosities of two industrial lead blast furnace slags have been experimentally determined as functions of composition and temperature. A Brookfield viscometer with alumina rods and crucibles were used. Experiments were carried out between 1200 and 1573 K in an argon atmosphere with up to 5% addition of FeO, MgO, and SiO2 to the slags. Results showed that 1) the viscosities of two slags decreased with increase in temperature; 2) addition of FeO decreased the slag viscosities; and 3) addition of MgO and SiO2 increased the slag viscosities. Use of the above slag compositions with the addition of FeO is recommended for successful lead smelter operation.

Jan 1, 2005

By A. E. Reisenauer, R. W. Nelson, G. W. Gee

A model assessment was made to evaluate contaminant transport to ground water from clay-lined and unlined tailings pits. The input hydrologic soil characteristics were measured on materials typical of those found at the Morton Ranch uranium mill site in central Wyoming. The assessment involved combined saturated and partially saturated flow and contaminant transport models for two-dimensional cross-sections typical of the proposed Morton Ranch burial pits. Specifically obtained from the models were contaminant flow paths, the advancing contaminant flow fronts for sorbed and non-sorbed constituents, and travel times of contaminants along flow paths. Such results enable evaluation of the environmental consequences for the alternative control methods.

Jan 1, 1980

By William E. Souder, R. J. Evans

From time to time, major technological innovations arise that alter the time-honored ways of doing things. Such innovations can dramatically benefit society in terms of new products, increased outputs, reduced costs and general modernizations. However, the advent of these types of technologies is likely to be resisted because of their uncertain potentials, and because they disrupt established routines and industry patterns. This paper reviews the case history of water jet coal cutting, and assesses its potential to become a major innovation within the next decade.

Jan 1, 1983

By P. D. Tomlingson

Senior mining mangers that do not get directly involved in the quality of maintenance performance risk the profitability of their operations. Maintenance is not a stand-alone activity. It requires a production strategy that addresses the total life cycle of equipment from procurement to replacement and assures the fully cooperative, mutually supporting interaction of all mine departments. Only senior managers can assure this happens. This paper examines the strategies, policies and actions required to establish and sustain effective maintenance and the profitability that derives from it.

Jan 1, 2004

By A. W. Khair, J. A. Organiscak, M. Ahmad

This paper describes research that seas conducted on bit wear and respirable-dust generation. The investigation was performed by the US Bureau of Mines (USBM) and West Virginia University (WVU), a member of the Generic Technology Center on Respirable Dust. The USBM investigated wear, energy and dust characteristics of various conical bit designs when cutting rock. WVU studied the functional relationships between wear, cutting force, energy and dust of one type of conical bit cutting coal. The objective of the USBM study was to identify qualitative bit-selection guidelines. The objective of WVU's research was to determine optimum bit-replacement guidelines. Both research studies found that bit geometry (a function of bit design and wear) influences energy consumption and dust generation. Bit selection and replacement recommendations are given.

Jan 1, 1996

By T. O. Price

In 1969 Holosonics designed and developed a portable system for conducting acoustical surveys in metal mines, with lead-silver veins as the principal targets. Recently this system has been proven useful in describing rock structures for advance geologic information in civil engineering application and underground construction applications. This paper discusses a case history of acoustical surveying from a series of pilot drill holes in an advancing tunnel. In acoustical surveying a pulsed acoustic signal is used to generate reflected signals from the rock formation. Arrival time, amplitude and phase of the returned signals can be determined. These data became the basis for a signal correlation program designed to relate the signals to their respected pseudo-planar reflecting interfaces. An application of acoustical surveying has recently been conducted in a portion of the excavation for the Washington Metro Area Transit Subway. The data results and conclusions of the program are discussed in the paper. Acoustical surveying was successful in predicting the occurrence of major jointing and foliation plane shearing ahead of the tunnel advancement.

Jan 1, 1974

By V. Badaker, R. J. Sweigard, C. D. Barton, J. W. Stringer, J. M. Ringe, A. D. True, D. H. Graves

Field studies have demonstrated the relationship between the growth of high-value trees on surface mined land and the physical conditions of the root growth medium. Specifically, the survival and height of hardwoods grown on less compacted material are far superior to those grown on compacted material. Furthermore, studies have demonstrated that the physical condition of the root growth medium can be characterized by dry bulk density and penetrometer resistance and that these parameters are also related to tree growth measurements. Site indices are useful for evaluating and predicting the productivity and timber yield for a specific location. A method has been proposed to estimate the site indices for various tree species on reclaimed surface mined land as a function of the physical properties of the root growth medium.

Jan 1, 2005

By V. Fred Swanson, J. Patrick Glynn

The environment for process engineers today is very different from 20 years ago. The ideas and mathematical description of models for a multitude of different unit operations is an ongoing development. The computer tools to deal with the mathematics are readily available and specialist companies have developed, tested and verified their models. The challenge for the process engineer is to know which package to use and to know whether a particular application is the most accurate for the specific process. Metallurgical simulation programs today are well known and proven. Certain programs are specialized while others are broader based. The needs of each user are dependent on the application. Typically, most users require the following operations: • Comminution • Flotation • Hydrometallurgy • Pyrometallurgy • Additional requirements could be defined as: • Thermodynamic capabilities for solids, phases, and gases • Dynamic simulation • Data analysis tools • Coal oriented operations • Diamond oriented operations

Jan 1, 1997

By A. J. Douchane, J. M. Shirley

The high grade gold and silver Ken Snyder Mine is located in north-central Nevada, in Elko County, adjacent to the town of Midas, approximately 240 miles to the east­northeast of Reno and approximately 60 miles to the northeast of the town of Winnemucca. The Midas Joint Venture (MJV), an equal partnership between Franco-Nevada Mining Corporation, Inc. and Euro­Nevada Mining Corporation, Inc. with Franco-Nevada Mining Corporation, Inc. being the joint venture manager, owns the mine. In May 1997, Kilborn Denver, now SNC-Lavalin America, completed a bankable feasibility study and proceeded with detailed design, procurement and construction management. In mid December 1998, MJV not only poured their first gold several months ahead of schedule, but were already operating at full production. In addition, the construction of this US $84 million mine, mill and related facilities were completed on budget. Operating cash costs are US $78/oz. This paper describes how this was accomplished.

Jan 1, 1999

By A. Goulsbral, D. Harrison, R. Dunne

A programme to reduce cyanide consumption at the New Celebration Gold Mine, situated 32kms South of Kalgoorlie, Western Australia, commenced in the latter part of 1990. Cyanide speciation studies at the time identified that the major loss and consequently consumption was due to the hydrolysis of cyanide, The use of artesian hypersaline waters of high magne­sium content on gold plants in Western Australian Goldfields has meant that economically viable operating pH values during cyanide leaching are around 8.9 to 9.5. The high ionic strength in these waters does to some degree retard the hydrolysis reac­tion. Notwithstanding this, the formation of hydrogen cyanide and its loss due to volatilisation is the cause of the major loss of cyanide on most gold plants in the Kalgoorlie Goldfields. This paper discusses the aspect of oxygen addition during cyanide leaching to decrease cyanide consumption and increase gold recovery.

Jan 1, 1996

By L. Korkiala-Tanttu, M. Rinne, Z. Song

Disposal of mine tailings has been recognized as an unavoidable burden of mining companies and local authorities. Conventional methods dispose mine tailings in a passive manner which hardly generates any value from them. On the other hand, growing local communities close to mines need more infrastructures which require great amounts of raw materials. In view of the above mentioned situation, a novel utilization of mine tailings is explored as alternative material for asphalt pavement, in order to extract more value from mine tailings and solve the high cost of pavement material. Inherent physical properties of the mine tailings were first investigated to find out their availability as pavement material. Then test specimens were made as mixture of the mine tailings and other pavement material to be tested in laboratory. The mine tailing materials presented a considerable potential as asphalt filler for low-volume roads. Furthermore, the limitat

Jan 1, 2011

By J. Maiti, A. Bhattacherjee

A literature review on quantitative analysis of mine safely studies revealed that numerous investigators explored a wide- range of techniques, including the investigation of bivariate and multivariate statistical models. Although these researchers addressed various issues of accident causation and prevention, they, in general, did not investigate through the use of quantitative models the multivariate relationships of several factors affecting mine safety in a causal framework. In this paper, systems dynamics and structural equation modeling are presented to simultaneously represent and study the effect of policy variables related to accident prevention along with the factors causing accidents and injuries. The application of these models to a group of mines revealed that current training practices at these mines do not appear to alleviate accident occurrences. It is inferred that the use of these quantitative techniques can provide a new direction of research in mine-safety studies.

Jan 1, 2000