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By T. Motzer

Sustainability management and reporting plays an important role in controlling and communicating a company's efforts in sustainable development. A variety of standards comprising a multitude of indicators often require similar information but with different data quality, level of detail and coverage. This may lead to inconsistencies in external communication because of the difficulties in collection and aggregation of data from different company sites and organisational levels. Using a central database system accessible via internet makes the process of data management more efficient: All relevant information can be collected on-site, with a defined data quality, credibility and consistency. Any type of sustainability indicator can be calculated automatically, once the data is collected. Individual analyses and predefined reports, e.g. GRI G3, can be easily generated and immediately published, making your sustainability communication transparent and reliable.

Jan 1, 2007

By Don Minard

Management support systems are extremely important to mining management to enable them to operate their company as a business. Management must give attention to the financial, maintenance, materials, and other reporting and control systems that are necessary to successfully operate a mining company. This subsection describes the management support systems that are critical to most mining companies. In this introductory review, the major objectives and functions of these management support systems will be introduced. The following topics will expand on the functions and key concepts as well as other considerations in each of these systems areas. Additionally, this introductory review will touch upon the unique environment that mining companies find themselves in from a management and personnel standpoint and the effect of this environment on management systems. Additionally, specific keys to successful systems installations and acceptance in the mining industry are discussed.

Jan 1, 1979

By Bernard J. Reddy

This paper describes in detail the economic forces affecting cobalt supply, demand, and prices. The major factors that will determine the growth or decline in the use of cobalt in each of its applications are discussed. The flows of cobalt from mine to refinery are described on a company-by-company basis. The paper concludes with a discussion of how the characteristics of the supply and demand sides of market interact to determine cobalt prices.

Jan 1, 1986

By Douglas W. Fuerstenau, Douglas M. Deason

The depletion of high grade siliceous phosphate ores is bringing about a search for economically processable replacements. The processing of unexploited dolomitic sedimentary phosphate reserves has numerous problems including the similar surface properties of the carbonate and phosphate minerals and the presence of significant concentrations of dissolved species in the flotation pulp. In this paper, inorganic adsorption and surface transformation phenomena exhibited by the dolomite/apatite systems are examined in detail. Electrokinetic, adsorption, and flotation results indicate that when placed in a common solution, these two minerals interact significantly, with a corresponding strong influence on flotation using a physisorbed collector. Such behavior can have strong implications for flotation plant practice.

Jan 1, 1993

By C. J. Bise

Continuous mining accounts for about 69% of the nation's underground coal production. This level is not expected to change much in the near future. This is because continuous mining represents the primary means of under- ground coal production. It is also the primary means of driving development entries for underground coal mines, including longwall mines. The continuous miner worksite contains many characteristics that can lead to personnel accidents. It continues to be an area of concern for mine managers, safety engineers, and training coordinators. In an effort to assist mine management in attempts to reduce the number of accidents and injuries sustained in this area, this paper presents a loss-control-based, non-intrusive strategy for conducting safety evaluations at continuous miner worksites.

Jan 1, 1991

By B. H. Richard, P. J. Wolfe, T. G. Holdeman

Guided seismic wave propagation was studied in the Lower Freeport (6A) coal seam in the Oak Park No. 7 mine near Cadiz, OH. Three component geophones were implanted in the coal at distances ranging from 72 m to 183 m from the seismic source. Both Love- and Rayleigh-type modes were observed but the Love-type mode produced the best data. Detailed analysis was performed on the best Love data and a Dziewonski map of group velocity vs. frequency was constructed. This map was in excellent agreement with a theoretical dispersion curve calculated for a model of the coal seam. The Love wave group velocity was found to have a minimum value of 510 m/sec at 275 Hz. Only the fundamental mode contributed significantly to the observed signal and it was observed up to the maximum distance available.

Jan 1, 1987

By Xinyang Xu, Jirun Xu, Changlie Deng, Kang Yan, Luo Qian

Cake filtration is a complex process and the cake constructure is very difficult to describe in theory. Cake constructure parameters, such as the cake prosity, pore size shape and even its distribution, are main factors influencing the filtration results but have not been thoroughly understood yet. In this paper the fractal theory, an effective mathematical method in describing the self-similar phenomenon is used to investigate the filter cake constructure, and the scanning electron microscope and automatic image analyzer are used to measure the cake constructure. Cakes which formed in different condition are examined and the fractal dimension of the cake are calculated. The study shows that the constructure of the filter cake can be approximated by Sierpinski fractal geometry and that the fractal dimension of filter cake, related to the particle characteristics, slurry concentration and filtration pressure is a good parameter to describe the pore size distribution and the cake penetrability.

Jan 1, 1995

By Robert G. Benson, David M. Jones

The San Luis deposit of Costilla County, Colorado contains 11,021,000 tonnes (12,149,000 tons) of ore at 1.4 g/t (0.040 oz/st) gold in two mineable zones. Gold mineralization is associated with silicification and quartz-sericite-pyrite alteration localized in breccias along a low-angle "detachment" fault zone in Precambrian gneiss. Gangue minerals include chlorite, specularite, chalcopyrite, molybdenite, and fluorite. Mineralization is mid-Tertiary in age and may have an indirect genetic relation to the emplacement of felsic intrusions. Portions of the ore body are unconformably overlain by sedimentary rocks of the Tertiary Santa Fe Formation. The deposit formed during the early stages of extensional tectonism along the eastern edge of the present day Rio Grande rift.

Jan 1, 1990

By B. E. Dindsale, P. B. Altringer, R. H. Lien

The Bureau cf Mines, U.S. Department of the Intericr, is investigating biolcgical and chemical deccntaminaticn of cyanide- containing leachates and residues. Biolcgical cyanide cxidaticn, using bacteria isolated from a precious metals tailings pond, destroyed >85 pct of the cyanide in several prccessing solutions containing up tc 280 ppm CN. Reaction time varied from about 4.5 hr in a trickling reactor using quartz as a bacterial substrate to 2 mo in unagitated, covered flasks. Chemical techniques were used to destroy the remaining complexed cyanide down to 1 ppm. Exploratory tests were also conducted using spent ore from heap leach operations as the bacterial substrate to determine if biological cyanide oxidation could be used to destroy the residual cyanide in spent heaps.

Jan 1, 1991

By J. A. Herbst, K. N. Han, P. B. Queneau, S. W. Asihene

As hydrometallurgy matures as a technology, more of its existing process knowledge will continue to be summarized in the form of detailed mathematical models. This development is happening at a time when major improvements in computer hardware have reduced the cost of computing. The opportunity then exists, through the solution of these process models, to design, control, and optimize hydrometallurgical plants on the basis of the physics and chemistry of its processes and less on empiricism. In this paper, a review of the current capabilities of sensors and phenomenological models for selected hydrometallurgical processes is presented. Future trends, in terms of the control and optimization of hydrometallurgical plants, are then explored. The possibility of simultaneously optimizing plant design and associated process control system performance is discussed.

Jan 1, 1993

By R. Pazhianur

Many investigators conducted surface force measurements between hydrophobic surfaces in water, and observed attractive force that was substantially stronger than the van der Waals attractive force. The excess force was appropriately referred to as “hydrophobic force”, for which many different theories have been put forth by numerous investigators. In an earlier publication (Yoon and Ravishankar, 1996), it was suggested that the hydrophobic force maybe due to the interaction between the large dipoles created by the surfactants adsorbing on solid surfaces in patches (or domains). In the present work, a mathematical model has been developed to further elaborate the theory.

Jan 1, 2003

By K. Gum, W. C. Hirt, D. A. Rice

Selective flocculation was used to produce a superclean zinc concentrate by minimizing silica contamination. Research was carried out on a flotation concentrate from the Jersey Miniere Zinc Company (JMZ) in Gordonsville, TN. The material was first dispersed with sodium silicate and then causticized tapioca starch was used to selectively flocculate the sphalerite, leaving the silica in suspension. This technique has been applied commercially to iron ore beneficiation but never to zinc processing. The feed material assayed 0.45% SiO2. The use of 0.56 kg/ t (1.13 lb/st) sodium silicate and 0.070 kg/t (0.141 lb/st) causticized tapioca starch resulted in a 98.2% zinc recovery and produced a purified zinc concentrate assaying 66.0% Zn and 0.24% silica. The target level for silica contamination in JMZ zinc concentrates is currently 0.30% Si02. This work demonstrated that selective flocculation is a potential method for cleaning flotation concentrates, particularly where low silica products are required.

Jan 1, 1995

By I. G. Ediz, D. W. Dixon, W. M. Fidler

In this paper a new method for the arresting of tunnel explosions is presented. In the proposed technique, the on coming explosion is detected by a pressure sensitive device by a pre-determined rise in static pressure. The sensor then triggers a mechanism which causes the explosion door to be closed in a specially constructed concrete barrier zone. The doors are of a special construction and consist of perforated steel plates that allow part of the blast wave to be transmitted but do not allow the passage of the flame. A number of design parameters have been identified, including: the likely amplitudes of the transmitted/reflected pressure waves that would govern the explosion door pressure loading; thickness of the perforated steel packages; perforation dimensions; heat transfer across the door and other factors.

Jan 1, 1995

By O. A. Bascur

The problem of setting the proper control objectives and/or having several objectives to be met in the implementation of grinding control strategies can be resolved. The design and implementation of a distributed control system for safe operation of a grinding circuit while maximizing profit is presented. An optimal recovery through- put target for a desired grind is accomplished by advanced control strategies at the DCS level. A mill load constraint control technique provides stable operation with a substantial increase in throughput, while the desired grind index is maintained by an inferential grind control technique without using a particle size analyzer. The integration of crushing/grinding and flotation in the overall design was the key to the success of the project. This synergistic effect was obtained by implementing a computer plant management system in the concentrator. The overall/philosophy was to keep the implementation simple while using new technology creatively.

Jan 1, 1991

By Michael G. Nelson

A computer simulation of the automatic control of continuous mining machines has been prepared, similar to previous simulations of longwall mining systems and coal thickness sensors. The simulation allows for programmed variation of the horizon detection method, the azimuthal guidance system, the type and configuration of the miner, varying hardness in the unmined face material (leading to varying error in the machine heading), and the miner's cutting cycle. It simulates control of the miner in three axes. Use of the simulator makes it possible to anticipate problems arising from the complex character of underground mining, which include unpredictable multi-pass coupling and unpredictable variation in geological conditions.

Jan 1, 1993

By O. Akinkugbe

The safe, productive exploitation of coal in multiple-seam situations requires specific design technology. At present, there are two general design approaches that the mining engineer can use to analyze the multiple-seam problem in question, either simple empirical relationships or complex numerical models. Often, the empirical approaches are too general for the specific problem and the numerical models require too much time and expertise for the practicing engineer. In this paper, a new program designed for quickly and easily calculating the stresses, strains, and safety factors associated with basic multiple-seam mining situations is presented. The program implements a simplified, two-dimensional boundary-element method in order to model the complex multiple-seam stress and displacement interactions. The program incorporates automatic coal and gob property generation to simplify the input, and inherently calculates pillar safety factors to enhance the output.

Jan 1, 2004

By Gregory W. Gustina, Terry P. Boyle

Analysis of the structure of the benthic macroinvertebrate community, consisting of the number of taxa and the relative distribution of total numbers, is a routine method of assessing the ecological quality of streams. Various multivariate statistical techniques, which assess the structural variability of the benthic macroinvertebrate community and the relationship of that variability with natural and anthropogenic environmental variables, have utility in separation of the various physical and chemical factors associated with impact. Multivariate methodology, while computationally complex is statistically rigorous and better integrates physical, chemical, and biological data for more synthetic interpretation. Using the multivariate analysis technique, canonical correspondence analysis, we have analyzed a number of sites in the upper Boulder River Basin, Montana to determine which are the important environmental variables associated with variation in community structure. The results of this analysis an integrated with more traditional analysis of community structure and incorporated in a risk analysis for the mediation of abandoned mines and mill sites within the watershed.

Jan 1, 2000

By M. Takayasu, J. Y. Hwang, F. J. Friedlaender, G. Kullerud

Al unite has been used as raw material for producing alumina and potassium sulfate fertilizer in Russia for many years. In the United States, this mineral has not been commercially processed though reserves of 5 to 10 billion tons of alunite ore have been estimated. Major constituents of these ores are quartz and alunite. The minerals are finely intergrown and liberation occurs below 10 µm. Adequate separation techniques for such ultrafine particles have not been developed. A new method for the beneficiation of al unite ore is proposed in this study. This method utilizes a small amount of fine magnetite upon which the liberated quartz is selectively flocculated. The co-flocculated magnetite and quartz are then separated from the alunite in a high gradient magnetic separator. Clean products, e.g., an al unite concentrate of 90% grade with 80% recovery, has been obtained from Utah ore. Techniques for selective co-flocculation of magnetite and quartz, separation of the carried quartz, and recovery of magnetite after separation are discussed.

Jan 1, 1987

By Richard Engelmann

The mining industry, in particular the coal industry, has experienced the implementation of some major environmental regulatory programs during the past two decades. Over the coming decade the coal industry will probably experience only "fine tuning" of the regulatory programs they now operate under. The rest of the indus- try, however, appears to be on the verge of coming under a major new regulatory effort by the Environmental Protection Agency. Litigation and resulting court decisions will be the main force driving further changes in the SHCRA (Surface Mine Control and Reclamation Act) regulatory program. These changes are anticipated to be minor in compar- ison to earlier changes. EPA, however, is preparing a regulatory program which may carry as much impact to the rest of the mining industry as SNRA was to coal. Details of this program have yet to be worked out. Changes in the way EPAts Clean Air Program is applied to mining could also significantly impact the mining industry.

Jan 1, 1989

By F. T. Paleari, J. A. Finch

Radial gas holdup profiles were measured in a 50-cm-diam, 400-cm-high flotation column using a multi-cell-conductivity probe. Three bubble-generation systems, including a system with up to eight vertical filter-cloth spargers, a system with three horizontal filter-cloth spargers and a system with three (horizontal) Cominco-type spargers, were examined. The variables investigated were the number of spargers, the symmetry of their arrangement and the height above the spargers. Batch water containing up to 20 ppm frother was used. Generally, the profiles tended to be uniform (flat) with some profiles exhibiting a slight "wavy" pattern. The vertical sparger arrangement proved to be the most difficult in which to achieve a profile symmetry. The horizontal spargers gave uniform profiles at right angles to their length but gave decreasing gas holdup along their length. The Cominco-type spargers gave slightly less scatter in the data. Switching off selected spargers to simulate a malfunction did not produce strong asymmetry in the profiles.

Jan 1, 1995