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By Don Stainbrook

Over a period of many years a highly automated computerized system of ore control has been developed at the Newmont Gold Company, (NGC). It is the purpose of this paper to review the development of this system, describe the setting in which it functions and to mention some of the future developments and enhancements. Discussion of the evolution of the system in a historical perspective helps to understand its present status and illuminate some thinking about future directions of development.

Jan 1, 1989

By S. B. Bhagwat

Before the Clean Air Act Amendments of 1990, coal policies-especially coal research policies-were geared to find a solution to the sulfur emission problem. However, technologies to reduce sulfur emissions cannot be tailored for a single coal. A technology that will clean Illinois coal to compliance levels will do the same, or nearly the same, for most other types of coal. This paper will discuss an integrated approach to the analysis of the future of coals from different regions in the United States and its implications for coal-related policies by government and industry.

Jan 1, 1994

By W. Z. “Ben” Wu

The investigation provides a method of efficiency evaluation among several kinds of tools employed to cut different types of rocks. A ballistic test stand incorporated with a modified Hopkinson bar was used to simulate a percussive drilling tool. An Apple IIe microcomputer was employed for high speed data acquisition and numerical analysis. A newly developed method for remote monitoring the rock-tool interaction, including contact force, bit penetration and energy transmission,is presented in the paper. Theoretical predictions and experimental results appear in faily good agreement

Jan 1, 1986

By Ing. Alois Adamus, Ing. Václav Pošta, Ing. Lubomír Hájek

This paper reviews experiences connected with the use of nitrogen in the Czech coal industry. Special attention is focused on the first use nitrogen In the Czech Republic, it is probably the first case of fighting a mine fire using nitrogen in all the World. Discussion dwells on the present-day use of nitrogen, its sources, consumption, technological equipment, and the theoretical evaluation of nitrogen flushing.

Jan 1, 1995

By José Salim, T. V. Subrahmanyan

The occurence of primary stratiform and vein gold deposits in the Precambrian rocks of Northeastern Brazil is discussed. The stratiform deposits are related to clastic sediments (quartzites and conglomerates). The veins are associated with quartz and sulfides and are structurally controlled by shear zones. The gold was recovered for a long time by small miners. Developmental programmes for large scale mining are now envisaged. The recovery problems and gold economics are also discussed.

Jan 1, 1988

By Surendra K. Mishra

Recent land ban act has put pressure on industry to decontaminate the waste streams before they could be discharged. However, for both metal and organic contaminated wastes, there are commercial incentives to recover usable resources. Recent technology developments have helped meeting such objectives. This paper reviews developments in treatment technologies for industrial wastes. Major chemical groups used in waste treatment are summarized.

Jan 1, 1994

By K. S. Shivakumar, R. Bhima Rao, M. R. Patil

Liberation size can be estimated using various techniques such as grain counting, frequency curves, X-ray intensity and the mesh of grind. The present investigation deals with the estimation of the liberation size of graphite flake contained in a schistose ore from Shivaganga, India. It was observed that the flakes are liberated at from 75 to 150µm. The rougher flotation concentrate obtained after grinding the run-of-mine ore for 5 min contained 54% fixed carbon. This represented the first stage of liberation. After regrinding to <90 µm in the presence of sodium silicate and guar gum, a cleaner concentrate containing 82% fixed carbon was obtained.

Jan 1, 1998

By S. J. Jung, F. Lock

This research came about because of the recognized need for a safe, easy way to line small-diameter bored raises (less than 150 cm). Currently, an operator must go down the raise and apply the concrete lining manually, using the shotcrete method of application. With an automated system, there would be no man positioned in the bore itself. All control functions could be commanded from a central location. Shotcreting in the confined space of a small-diameter bored raise presents problems that can be overcome by the application of shotcrete using a remote system.

Jan 1, 1995

By Mark W. Springett

The sampling of precious metal deposits entails inherent problems due to the low mineral abundances, high mineral specific gravities, skewed grade distributions and wide ranges of mineral particle sizes. Sampling practices and precautions are discussed with particular attention to each of the tripartite stages of sampling - sample acquisition, sample preparation and sample assaying. Practical examples of approaches to the sampling problem are given and some examples of significant sources of error are provided from gold and silver deposits in North America.

Jan 1, 1992

By R. C. Guimareãs

Serrana&apos;s deposit contains three types of ore: oxidized, micaceous and silicate-carbonate. The results presented refer to characterization and fundamental studies performed on fractions resulting from the purification of five samples from the silicate-carbonate type collected in the mine. Each type was purified and submitted to mineralogical characterization, zeta potential determinations, and microflotation experiments. The samples, with exception of the barite, are mineralogically complex and the selectivity between apatite and gangue minerals is poor. Under the current state of art, it is impossible to feed the plant with the silicate-carbonate ore, unless it is blended with the standard oxidized ore.

Jan 1, 2002

By G. D. Hood, B. E. Davis

A fundamental study of the mechanisms involved in the conditioning of coarse Florida phosphate has led to some interesting discoveries. Studies by the US Bureau of Mines have shown that conditioning time and mixing intensity greatly affect the grades and recoveries of the phosphate minerals and quartz in the rougher concentrate. In particular, as the conditioning time or mixing intensity increased, the phosphate recovery remained constant while the amount of quartz floated decreased. This phenomenon is contrary to conventional wisdom and could lead to a more efficient coarse flotation circuit.

Jan 1, 1995

By L. D. Gehi, A. W. Khair, M. Ahmad

This paper presents an analysis of the effect of the dynamics of bit wear on dust generation. Two surveys have been conducted in order to assess the mechanism and type of bit wear and to evaluate the impact of bit wear on the productivity of the continuous miners. Used bits were collected from the underground coal mines and these used bits were utilized in laboratory coal cutting. The effect of bit wear on dust generation has been quantified and its impacted on dust generation and ventilation system has been exemplified.

Jan 1, 1993

By James R. Arnold, Timothy D. Arnold

The mathematical rigor of the collegiate engineering experience prepares an engineer well for the technical aspects of his or her career. However, as that engineer progresses in the industry, how well does he or she do as a manager? The exacting, detailed, and complete problem-solving process that engineers are trained to use sometimes conflicts with the nimble, rapid decision-making process required in the dynamic world of business. This paper discusses the topic of "engineers as managers.”It will investigate the personality traits of engineers relative to the traits of successful managers, and provide specific details about how well engineers have done in the field of management.

Jan 1, 2001

By R. M. Carland, F. F. Aplan

Six natural zeolites were evaluated for their ability to selectively remove heavy metal cations from solution. Ion selectivity was found to be Pb+2>Zn+2>Ni+2 and Cu+2>Co+2 from their respective solutions. The presence of K+, Ca+2 and Mg+2 in the actual waters to be used may seriously interfere with the ion exchange and elution of cations from zeolites. Zeolites were found not to be effective in removing precious metals from their cyanide solutions.

Jan 1, 1995

By Louis W. Cope

The various types of placer deposits will be described as an introduction to the subject. The several methods and machines used for sample taking and processing will be discussed. The advantages and disadvantages of each will be covered. Included will be mistakes and pitfalls of placer sampling and sample reduction.

Jan 1, 1987

By William J. Attwooll

The development of gold heap leach projects in the Cripple Creek, Colorado, mining district has required utilization of heap leach pad sites other than relatively level natural ground. This paper describes the construction of a heap leach pad adequate to accommodate 907,000 tonnes (1,000,000 st) of ore over the surface of a tailings pond constructed during previous milling activities at the site. Based on the design parameters and the observed behavior to date, it has been found feasible to construct a major heap leach pile on the surface of a conventional tailings pond.

Jan 1, 1987

By Wen-Long Cai, A. Frederick Banfield

This paper investigates, through case studies on a porphyry copper and a coal deposit, the differences and relevances between an approximate production schedule approach, i.e., the best case and the worst case schedules and a practical production schedule approach. The comparisons were with regards to: 1) choosing an optimum ultimate pit size, 2) determining processing capacities, 3) selecting &apos;optimum&apos; cutoff grades, and 4) blending. The comparison criteria was to maximize the project net present value. Conclusions were drawn based on the study results.

Jan 1, 1996

By Park. D. W., Y. M. Jiang, L. A. Morley, W. Keeton

Underground room-and-pillar mining operations in the Warrior Coal Field in Alabama frequently suffer instability due to soft floors and thinly-laminated immediate roofs. This investigation concerns a mine that was experiencing ground-control problems with weak floor conditions. Several roof falls occurred locally, and as much as 0.6 m (2 ft) of floor heaves have been experienced. The paper presents the results of comprehensive analyses conducted on floor heave, roof sagging, pillar- penetration and floor bearing capacity using instrumentation and numerical modeling.

Jan 1, 1993

By Michael L. Nave

An existing coal mine&apos;s raw coal 60 inch conveyor system had become productivity bound by a capacity of 3,500 tph. The existing conveyor drives were fixed speed wound rotor induction motor drives installed in 1983. The fast track upgrade installed variable speed medium voltage variable frequency drives to speed up the conveyor to a capacity of 5, 000 tph. The installation took place over a one week system shutdown during Christmas 2000.

Jan 1, 2002

By Y. H. Chia, P. Somasundaran

Carrier flotation of anatase from clay using coarse calcite is investigated, together with relevant basic properties of the system including aggregation and zeta potential, under different chemical and hydrodynamic conditions The roles of carrier sue and amount also are considered Mechanisms responsible for selective aggregation and flotation are reviewed

Jan 1, 1983