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By S. D. Thompson, J. C. Dzurino

This investigation mainly focused on designing a bunker system for a large underground coal mine. The primary purpose of this bunker system was to keep high- and low-sulfur coal segregated on the underground belt system. These bunkers were also required for protecting the mine faces from out by belt delays. Methodologies used in developing this plan are briefly discussed. The final design and the procedures formulated for implementing it are also presented.

Jan 1, 1987

By W. F. Quirk

The Missouri-Oklahoma tripoli district was discovered and first mined in 1869 near Seneca, Missouri. Tripoli is a microcrystalline form of high-purity silica that is porous, light- weight, and friable and is derived from a parent siliceous sedimentary rock from which soluble minerals have been leached. Tripoli deposits, 2 to 20 feet thick, occur in cherty limestones of Mississippian age beneath 2 to 10 feet of overburden. They are mined in open pits up to 9 acres in size. The color of tripoli is white, but it also commonly is light pink or red where stained by red iron oxides and clays. Ground tripoli is used commercially as an abrasive or in buffing and polishing compounds and is prized for such physical characteristics as its abrasiveness, porosity, permeability, absorption, and specific gravity.

Jan 1, 1978

By Li Honggui, Liu Maosheng, Zhao Zhongwei, Sun Peimci, Li Yunjiao

Leaching of Shizhuyuan low-grade refractory tungsten ore was carried out in a mechanically activating reactor. The effect of experimental parameters-temperature, amount of Na2C03, addition of NaOH, ratio of liquid to solid and leaching time - on the recovery of WO3 was studied. The WO3 recovery up to 96.99% have been achieved when the tungsten ore was digested by soda not more than three times the stoichiometric amount at 185-195°C for 1 .O-2.0 hours. Iso-extraction countour diagrams were drawn to illustrate the effect of various parameters on leaching. The WO3 recovery could be expected to increase 10-15% compared to that of conventional soda autoclave process.

Jan 1, 1995

By Lee Herold Storey

Groundwater remediation is growing in occurrence in the western United States. Groundwater remediation programs are regulated by state water quality statutes. The remedial action plans implemented under these statutes may conflict with well-established existing rights to withdraw groundwater for beneficial use. This paper discusses how the states of Arizona, Colorado and New Mexico administer conflicts between the need to withdraw and remediate groundwater with the existing rights of others to withdraw groundwater for beneficial purposes.

Jan 1, 1991

By S. Dessureault

Integrated information technology infrastructure is the linking of data across various applications throughout a business to gain further data-driven improvement opportunities. Decision support systems (DSS) are the various improvement opportunities that facilitate decision making for a potential optimal outcome. Integrating tera-bytes of data spread throughout a business is complex. There are tools to facilitate the development of such data-driven DSS. This paper analyzes the various tools that may facilitate the development of complex data-driven decision support systems, namely; information models, business models, data utilization model, and testing environments. A case study is presented to demonstrate how these tools facilitated the development of an automated activity-based budgeting DSS at a large-scale underground mining complex.

Jan 1, 2004

By S. R. S. Sastri, K. K. Bhattacharya, K. S. Narasimhan

Experimental results obtained on the recovery of below 0.5 x 10-3m coal fines by flotation employing geometrically similar columns of 0.056m, 0.080m, 0.100m and 0.220m diameter have been presented. The hydrodynamics of such a unit as well as its performance have been related to operating parameters to establish optimum conditions. The results have further been analysed critically in the light of the known relationship on the behaviour of similar systems to assign reasons for the critical factors established in a bid to reduce the empiricism required to be followed in the scale up of such a unit.

Jan 1, 1988

By Gabriel Babut, Ion Matei, Roland Moraru

Several controlled recirculation systems are in operation wor1dwide. As an unconventional technique of ventilation the implementation of such a system requires particular safety conditions and a well-founded set of feasibility factors and parameters. On the other hand, many mines in Romania are facing problemms in meeting the growing ventilation demands, so that controlled air recirculation could give an answer. The present paper presents the results of the work in this field, based on a detailed theoretical approach. Parameters wich must to be taken into account were identified and analysed, numerical simulation are carried out and an experimental test-scale model is presented.

Jan 1, 1997

By Alan M. Ritchie, Paul Miskelly

The 2-D code FIDHELM has been used to simulate conditions in piles of pyritic material with vertical dimensions of 20 to 70 m and a horizontal dimension of 500m. Those properties of the pile and its external environment (wind, temperature) important in determining the time and space dependence of sulfide oxidation, have been identified. A prescription to evaluate the overall sulfide oxidation rate in a pile of known volume but variable geometry has been developed.

Jan 1, 2000

By Jerry Dollinger, Levent Ozdemir

An extensive series of laboratory cutting tests using linear and rotary cutting machines were carried out with the objective of investigating the feasibility of achieving very high rates of penetration with TBMs in rocks of low to medium strength. These tests were performed with large diameter disc cuttrs at cutter path spacings and penetrations of up to 12 and 1.75 inches, respectively. A predictor model was also formulated to characterize rock cutting at large spacings and penetrations.

Jan 1, 1987

By Michael W. Glasson, Archie M. Richardson, Leo Gilbride, Laine Adair

Andalex Resources, Inc. recently engaged in a ventilation planning exercise that resulted in the construction of a new main fan installation to support longwall coal mining at the Aberdeen Mine. This paper documents the planning process, including underground measurements, modeling, permitting, and construction of the new fan installation.

Jan 1, 1997

By I. W. Farmer, R. E. Finky

Design of structures in rock based on ultimate limit states or strength criteria is unrealistic. The fracture process which inevitably occurs in rock around an underground structure is an energy release phenomenon. The development of fractures and associated displacements around a structure may therefore be more logically described using strain energy concepts and design may sensibly be based on serviceability limit states.

Jan 1, 1986

By Jeff Schwoebel, Dale Evans, Boyd Tangren

The Soldier Canyon Mine (the "Mine") degasification project demonstrates the ability to commercially recover coalbed gas to reduce overall mine costs associated with methane drainage. Gas is recovered from active and inactive areas of the Mine through an underground pipeline and surface compressors. Close inspection of gas quality is required due to potential contamination of air caused by excessive vacuum. Water must be removed routinely to enhance gas removal. This paper will review the operational and production procedures required to maximize gas recovery and insure safety at the Soldier Canyon Mine gas recovery project.

Jan 1, 1993

By M. J. Hrebar

This paper reviews large dozer stripping techniques and presents results of two field studies. The first is a seven-shift study of a contour block stripping operation where a Caterpillar DII is used as the primary stripping equipment. The second is a two-shift study of two Cat DIIs dozing blast cast material ahead of a dragline operation. Surveys and continuous time studies were used to determine production rates and as a basis for forecasting unit stripping costs in both cases.

Jan 1, 1994

By Walenty Frydel

The paper deals with highly efficient dust collecting systems of the 10-600 type which constitute new generation installations de- signed to eliminate dust hazard in headings driven with roadheaders. A vortex ventube controlling the air flow in the com- bined ventilation system by means of air vortex generated by the ventube drive unit is also presented. From the results of measurements of under-roof concentrations of methane it appears that the application of the vortex ventube makes it possible to decrease the under-roof accumulation of methane more than 10 times.

Jan 1, 1997

By Dae S. Young, Eleonora Widzyk-Capehart

A quantitative estimation of the size distribution of rock fragments is extremely important in mining, metallurgy and other geotechnical fields. This paper presents a new approach to the analysis of fragmentation. The method combines the practicality of digital image processing of the rock surface with the theoretical volume calculations based on the principles and laws of fractal geometry. The final volumetric distribution curve is compared with the results from traditional sieving indicating close agreement.

Jan 1, 1996

By Fathi Habashi

ION FLOTATION was introduced by F. Sebba in 1959. This technique permits the recovery of metal ions from solution through the introduction of an appropriate cationic or anionic surface-active agent into the solution. The surface-active agent, called a collector, is added in stoichiometric amounts in relation to the metal content of the solution. It reacts with the metal ion to form an insoluble soap, and is levitated to the surface by gentle bubbling of air to form a foam which collapses into an insoluble scum. The optimum conditions for the ion flotation with soaps of C10-16, fatty acids are shown in Table 15-1. Baarson and Ray (1965) found that once the metal was completely precipitated as the hydroxide, as little as one hundredth the stoichiometric amount of the collector was required to cause complete flotation of the [ ]

Jan 1, 1970

By S. Behl, S. Mathur

The viability of physico-chemical purification methods such as selective, flocculation for the separation of two components having similar chemical compositions and the same crystal structure but different surface properties is demonstrated. A loss of selectivity was observed in a dolomite-dolomite mixture when polyethylene oxide (PEO) (five million molecular weight) was used us the flocculant. Heteroflocculation was minimized using a low molecular weight PEO (MW =105) as a site blocking agent (SBA). Near complete separation was achieved at pH 10.5 at the 100% recovery level

Jan 1, 1996

By M. E. Gershon

An approach for scheduling the mining of ore and waste blocks in a surface mine is presented. While mathematical programming approaches have been developed to solve this problem optimally, they are difficult to implement and understand. The more simplistic approach presented here achieves practical mining schedules, taking into account both long- and short-term considerations. The key to the approach is use of the concept of ranked positional grade. The program can determine a complete schedule for a specified time period, or it can be used interactively as a guiding tool for the engineer.

Jan 1, 1988

By R. A. Womack, Alex Ruzycki

Over the past six years, 4.5 million tonnes (5.0 million short tons) of gold ore have been heap leached at the Alligator Ridge Mine. Ore is leached in successive lifts, resulting in heap heights of 20 m (66 ft). Recoveries from each lift are determined through an extensive post-leach drilling program. The relationships between heap height, recovery rate, ore preparation, heap construction, and leach solution application are discussed.

Jan 1, 1987

By A. Cecala, J. Noll, J. Hummer

"NIOSH has observed that many control rooms and operator compartments in the US mining industry do not have filtration systems capable of maintaining low dust concentrations in these areas. In this study at a mineral processing plant, to reduce respirable dust concentrations in a control room which had no cleaning system for intake air, a filtration/pressurization system originally designed for enclosed cabs was modified and installed. Eighty-seven percent of submicron particles were reduced by the system at static conditions, meaning that greater than eighty-seven percent of respirable dust particles should be reduced. The particle size distribution for respirable dust particles are greater than for submicron particles, and filtration systems usually are more efficient in capturing the larger particles. A positive pressure near 0.02 inches of water gauge was produced which is an important component for an effective system and minimizes particles (e.g. dust) from entering into the room. The intake airflow was around 118 cfm, which is greater than the airflow suggested by ASHRAE for acceptable indoor air quality. INTRODUCTION Chronic overexposure to respirable silica dust (particle diameter < 10 microns) leads to a progressive lung disease known as silicosis. Workers who develop silicosis have an increased incidence of lung cancer and pulmonary disorders. In June 1997, the International Agency for Research on Cancer (1) found sufficient evidence to declare that inhaled crystalline silica in the form of quartz and cristobalite is carcinogenic. Mining is one of the leading industries for occupational exposure to silica dust (2-7). Control rooms located in dusty areas in some mines are of particular concern (8). Many mineral processing operations utilize operator’s compartments and/or control rooms to house workers who are performing particular job functions. Most industrial processing mills have rooms where a worker looks out over the facility and has direct control over the product flow throughout the entire building. In addition, primary crusher operators are often located in a compartment from which they are able to view the primary crushing function. Their job is to control when trucks dump into the primary jaw crusher and the rate of feed of the ore from the hopper into the crusher. Many of these control rooms and operator booths do not have filtration systems capable of cleaning air entering the control room or booth, which can result in elevated concentrations of dust in the room or booth. To reduce the dust concentrations in these rooms, it would make sense to clean the entering air with filtration/pressurization units similar to those proven to provide a clean environment in enclosed cabs."

Jan 1, 2016