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Full-Text Articles in Mining Engineering

Niosh/Nci Study Of Exposure To Diesel Exhaust In Underground Mines — An Industry Perspective, Christopher J. Pritchard Jun 1999

Niosh/Nci Study Of Exposure To Diesel Exhaust In Underground Mines — An Industry Perspective, Christopher J. Pritchard

U.S. Mine Ventilation Symposium

In 1992, the National Institute For Occupational Safety and Health (NIOSH) initiated a study, funded by the National Cancer Institute (NCI), to evaluate the health effects, if any, involving underground miners exposure to diesel exhaust. An industry organization, the Methane Awareness Research Group (MARG) already in place to respond to gassy mine related issues, was redirected to work with diesel concerns. In 1995, NIOSH released a draft protocol and feasibility assessment, indicating its intent to initiate s study at 14 underground mines, some of which were operated by MARG members. After considerable debate on the study protocol, in-mine industrial hygiene …


A Mathematical Model Of Heat Transfer In Partially Insulated Airways In Deep, Frozen Ground Placer Mines, Sukumar Bandopadhyay, Hanguang Wu, Michael G. Nelson Jun 1999

A Mathematical Model Of Heat Transfer In Partially Insulated Airways In Deep, Frozen Ground Placer Mines, Sukumar Bandopadhyay, Hanguang Wu, Michael G. Nelson

U.S. Mine Ventilation Symposium

Large seasonal variations in the temperature of the ventilating air in mines in the arctic cause changes in the original thermal field through heat and mass exchanges between the air and the surrounding medium. These thermal interactions have major influence on climatic quality as well as on the stability of the mine openings. Thawing of walls and roof in mine airways can be reduced by various types of thermal-insulation. Application of thermal-insulation prevents deep thawing of the rockmass surrounding an airway. In this case, the mechanism of heat transfer around a frozen, underground airway would be much different. A model …


Rapid Evaluation Of Rock Thermal Parameters At The Lucky Friday Mine, Ian J. Duckworth Jun 1999

Rapid Evaluation Of Rock Thermal Parameters At The Lucky Friday Mine, Ian J. Duckworth

U.S. Mine Ventilation Symposium

In many hot mines a large portion of the total heat load is associated with the surrounding strata. In order to maintain acceptable underground environmental conditions, the mine heat load must be controlled by the ventilating airstream, and in certain cases by mechanical refrigeration. To compute existing, or future heat additions from the surrounding rock, certain parameters must be -determined. These parameters include the rock thermal conductivity, thermal diffusivity, and the geothermal gradient (with relation to a virgin rock datum). These rock thermal parameters are typically estimated from published literature, or evaluated by laboratory or in-situ measurements. Presented in the …


Foreword, Jerry C. Tien Jun 1999

Foreword, Jerry C. Tien

U.S. Mine Ventilation Symposium

No abstract provided.


Comparison Of Methane Concentrations At A Simulated Coal Mine Face During Bolting, Charles D. Taylor, Edward D. Thimons, Jeanne A. Zimmer Jun 1999

Comparison Of Methane Concentrations At A Simulated Coal Mine Face During Bolting, Charles D. Taylor, Edward D. Thimons, Jeanne A. Zimmer

U.S. Mine Ventilation Symposium

Strategies for monitoring methane levels during roof bolting in an extended cut entry were evaluated. Testing was conducted at the Pittsburgh Research Laboratory's methane test gallery. Operating conditions were varied and methane releases at the face and drill holes were simulated. Methane readings were taken at the face, and at locations outby the face. Results show that, when the major source of methane was at the drill holes, the highest methane readings were at locations on or 6.1 m (20 ft) inby the bolting machine. Methods for selecting better outby sampling locations, when the majority of the methane is released …


Methods For Dust Removal In Roadway Sections, Walenty Frydel, Marcin Steindor, Robert A. Jankowski Jun 1999

Methods For Dust Removal In Roadway Sections, Walenty Frydel, Marcin Steindor, Robert A. Jankowski

U.S. Mine Ventilation Symposium

Systems for dust extraction in roadway workings subjected to suction or forced ventilation are a combination of dust collecting equipment and facilities designed for ventilating the working. Such a combination of suitable equipment provides safe and effective dust removal and ventilation of a roadway working as well as is determinant of proper cooperation of the equipment a system is composed of. The development of effective dust collectors of wet type which provide safe operation under conditions of great exposure to coal dust and methane explosion hazards as well as of vortex ventubes allowing methane accumulations under the roof to be …


Personal Cooling In Hot Workings, Michael A. Tuck Jun 1999

Personal Cooling In Hot Workings, Michael A. Tuck

U.S. Mine Ventilation Symposium

The number of mines experiencing climatic difficulties worldwide is increasing. In a large number of cases these climatic difficulties are confined to working areas only or to specific locations within working areas. Thus the problem in these mines can be described as highly localised, due to a large extent not to high rock temperatures but due to machine heat loads and low airflow rates. Under such situations conventional means of controlling the climate can be inapplicable and/or uneconomic. One possible means of achieving the required level of climatic control, to ensure worker health and safety whilst achieving economic gains, is …


Effects Of Drilling Small Diameter Exhaust Shafts In A Gassy Longwall Operation, Tim Coleman, William Maloney Jun 1999

Effects Of Drilling Small Diameter Exhaust Shafts In A Gassy Longwall Operation, Tim Coleman, William Maloney

U.S. Mine Ventilation Symposium

As the title indicates, this paper deals with the ventilation of a gassy longwall mine through the use of small diameter exhaust shafts. Extensive background information is provided to show the evolution of the mine's ventilation system to correspond with changes in longwall mining techniques, particularly increases in face width. A description of the blind drilled shaft techniques, which proved to be the most economical ventilation choice for US Steel No. 50 Mine, is also included.


Shock Waves Generated In The Presence Of Barriers In Gas Explosions, Baiquan Lin, Shining Zhou Jun 1999

Shock Waves Generated In The Presence Of Barriers In Gas Explosions, Baiquan Lin, Shining Zhou

U.S. Mine Ventilation Symposium

This paper examines conditions that generates shock waves in a gas explosion through experiment. The result shows that the presence of barrier and thin film, which is similar to air door and stopping in underground coal mines, is very important for the generation of shock waves in a gas explosion. When there are physical barriers, the speed of transmission would be very fast and shock waves will result in the process; when the film is destroyed in gas explosion, shock waves will also appear which would result in an increase in explosion power. Therefore, in order to weaken the gas …


The Effects Of Offshore Mining Of Beach Quality Sediments On Nearshore Wave Climate, Frank R. Lonza May 1999

The Effects Of Offshore Mining Of Beach Quality Sediments On Nearshore Wave Climate, Frank R. Lonza

Civil & Environmental Engineering Theses & Dissertations

Coastal communities rely on the beaches to attract tourism, but these sources of revenue require maintenance, such as beach nourishment. In an effort to maintain these beaches without causing any detrimental results, research is conducted to determine what effects, if any, exist when mining for sand in offshore areas.

The U.S. Government is permitting the search for beach quality sands offshore but is also ensuring that such mining will not have adverse results to the nearshore wave climate. This study was conducted using a coarse grid bathymetric map to calibrate a numerical model developed by the Danish Hydraulic Institute (DHI). …


Comparison Of Toms And Avhrr Volcanic Ash Retrievals From The August 1992 Eruption Of Mt. Spurr, N. A. Krotkov, O. Torres, C. Seftor, A. J. Krueger, A. Kostinski, William I. Rose, Gregg J. Bluth, D. Schneider, S. J. Schaefer Feb 1999

Comparison Of Toms And Avhrr Volcanic Ash Retrievals From The August 1992 Eruption Of Mt. Spurr, N. A. Krotkov, O. Torres, C. Seftor, A. J. Krueger, A. Kostinski, William I. Rose, Gregg J. Bluth, D. Schneider, S. J. Schaefer

Department of Geological and Mining Engineering and Sciences Publications

On August 19, 1992, the Advanced Very High Resolution Radiometer (AVHRR) onboard NOAA-12 and NASA's Total Ozone Mapping Spectrometer (TOMS) onboard the Nimbus-7 satellite simultaneously detected and mapped the ash cloud from the eruption of Mt. Spurr, Alaska. The spatial extent and geometry of the cloud derived from the two datasets are in good agreement and both AVHRR split window IR (11–12µm brightness temperature difference) and the TOMS UV Aerosol Index (0.34–0.38µm ultraviolet backscattering and absorption) methods give the same range of total cloud ash mass. Redundant methods for determination of ash masses in drifting volcanic clouds offer many advantages …


Early Evolution Of A Stratospheric Volcanic Eruption Cloud As Observed With Toms And Avhrr, David J. Schneider, William I. Rose, Larry R. Coke, Gregg J. Bluth, Ian E. Sprod, Arlin J. Krueger Feb 1999

Early Evolution Of A Stratospheric Volcanic Eruption Cloud As Observed With Toms And Avhrr, David J. Schneider, William I. Rose, Larry R. Coke, Gregg J. Bluth, Ian E. Sprod, Arlin J. Krueger

Department of Geological and Mining Engineering and Sciences Publications

This paper is a detailed study of remote sensing data from the total ozone mapping spectrometer (TOMS) and the advanced very high resolution radiometer (AVHRR) satellite detectors, of the 1982 eruption of El Chichón, Mexico. The volcanic cloud/atmosphere interactions in the first four days of this eruption were investigated by combining ultraviolet retrievals to estimate the mass of sulfur dioxide in the volcanic cloud [Krueger et al., 1995] with thermal infrared retrievals of the size, optical depth, and mass of fine-grained (1–10 μm radius) volcanic ash [Wen and Rose, 1994]. Our study provides the first direct evidence of gravitational separation …


Experimental Testing And Modeling Of Automotive Automatic Belt Tensioners, Jiaxin Zhao, Clark R. Barker, Larry Oliver, William Breig, Joey Edson Jan 1998

Experimental Testing And Modeling Of Automotive Automatic Belt Tensioners, Jiaxin Zhao, Clark R. Barker, Larry Oliver, William Breig, Joey Edson

Mining Engineering Faculty Research & Creative Works

Automatic belt tensioners are used in serpentine belt drive systems in many automotive front end accessory drive (FEAD) applications. The dynamic characteristics of the tensioner must be well defined in order to accurately model the entire belt drive system for system simulation studies. In order to determine required tensioner performance parameters, six different configurations of a production unit were tested over a wide range of frequencies at two different amplitudes of the arm travel. Data was recorded to define the total torque generated by the tensioner as a result of the known input motion to which the arm was subjected. …


Stratospheric Loading Of Sulfur From Explosive Volcanic Eruptions, Gregg J. Bluth, William I. Rose, Ian E. Sprod, Arlin J. Krueger Nov 1997

Stratospheric Loading Of Sulfur From Explosive Volcanic Eruptions, Gregg J. Bluth, William I. Rose, Ian E. Sprod, Arlin J. Krueger

Department of Geological and Mining Engineering and Sciences Publications

This paper is an attempt to measure our understanding of volcano/atmosphere interactions by comparing a box model of potential volcanogenic aerosol production and removal in the stratosphere with the stratospheric aerosol optical depth over the period of 1979 to 1994. Model results and observed data are in good agreement both in magnitude and removal rates for the two largest eruptions, El Chicho´n and Pinatubo. However, the peak of stratospheric optical depth occurs about nine months after the eruptions, four times longer than the model prediction, which is driven by actual SO2 measurements. For smaller eruptions, the observed stratospheric perturbation is …


Detection Of Volcanic Ash Clouds From Nimbus 7/Total Ozone Mapping Spectrometer, C. J. Seftor, N. C. Hsu, J. R. Herman, P. K. Bhartia, O. Torres, William I. Rose, David J. Schneider, N. Krotkov Jul 1997

Detection Of Volcanic Ash Clouds From Nimbus 7/Total Ozone Mapping Spectrometer, C. J. Seftor, N. C. Hsu, J. R. Herman, P. K. Bhartia, O. Torres, William I. Rose, David J. Schneider, N. Krotkov

Department of Geological and Mining Engineering and Sciences Publications

Measured radiances from the Version 7 reprocessing of the Nimbus 7/total ozone mapping spectrometer (TOMS) 340- and 380-nm channels are used to detect absorbing particulates injected into the atmosphere after the El Chichon eruption on April 4, 1982. It is shown that while the single-channel reflectivity determined from the 380-nm channel is able to detect clouds and haze composed of nonabsorbing aerosols, the spectral contrast between the 340- and 380-nm channels is sensitive to absorbing particulates such as volcanic ash, desert dust, or smoke from biomass burning. In this paper the spectral contrast between these two channels is used to …


Stemming Technique For Loading Angled Holes Charged With Anfo, Michael David Wilkins Jan 1997

Stemming Technique For Loading Angled Holes Charged With Anfo, Michael David Wilkins

Masters Theses

"Little research has been published on stemming blast holes, particularly what happens during the process. Previous work has concentrated on the performance of the inert material to find the best way to seal the hole and retain the explosive energy, at the exclusion of determining what happens during the loading and stemming process. Such studies were carried out by Konya and Worsey.

The major problem with stemming studies is that rock is an opaque material, and the actual mechanisms involved during the stemming process cannot be viewed. For this reason, tests were performed using clear tubes to simulate a blast …


Constrained Moments Simulation Of Healthcare Capital Acquisitions, A. Narsing, Samuel Frimpong, J. Whiting Jan 1997

Constrained Moments Simulation Of Healthcare Capital Acquisitions, A. Narsing, Samuel Frimpong, J. Whiting

Mining Engineering Faculty Research & Creative Works

Summary form only as given. Two analytical techniques which evaluate capital acquisitions in healthcare are the method of generating system moments and Monte Carlo simulation. Generating system moments enables the user to determine an estimate of the expected cost from a user-supplied function. Furthermore, the user can determine, from a variance component analysis, the sensitivity of the user-supplied function to marginal changes in the random variables by expanding the function about its mean using the Taylor series expansion to the second order. Calculating the magnitude of partial derivatives of each random variable with respect to the user-supplied function indicates the …


Fractal Relationships And Spatial Distribution Of Ore Body Modelling, D. J. Kentwell Jan 1997

Fractal Relationships And Spatial Distribution Of Ore Body Modelling, D. J. Kentwell

Theses: Doctorates and Masters

The nature of spatial distributions of geological variables such as ore grades is of primary concern when modelling ore bodies and mineral resources. The aim of any mineral resource evaluation process is to determine the location, extent, volume and average grade of that resource by a trade off between maximum confidence in the results and minimum sampling effort. The principal aim of almost every geostatistical modelling process is to predict the spatial variation of one or more geological variables in order to estimate values of those variables at locations that have not been sampled. From the spatial analysis of these …


Remote Sensing Of Volcanic Ash Clouds Using Special Sensor Microwave Imager Data, David J. Delene, William I. Rose, Norman C. Grody May 1996

Remote Sensing Of Volcanic Ash Clouds Using Special Sensor Microwave Imager Data, David J. Delene, William I. Rose, Norman C. Grody

Department of Geological and Mining Engineering and Sciences Publications

Measurements from the satellite-based special sensor microwave imager (SSM/I) were used to collect passive microwave radiation (19–85 GHz) for the August 19, 1992 (UT date), Crater Peak/Spurr volcanic cloud. This eruption was also imaged by a ground-based C-band radar system at Kenai, Alaska, 80 km away, and by the thermal infrared channels of the polar-orbiting advanced very high resolution radiometer (AVHRR). The SSM/I sensor detects scattering of Earth-emitted radiation by millimeter size volcanic ash particles. The size of ash particles in a volcanic ash cloud can be estimated by comparing the scattering at different microwave frequencies. The mass of particles …


Measurements Of The Complex Dielectric Constant Of Volcanic Ash From 4 To 19 Ghz, R. J. Adams, Warren F. Perger, William I. Rose, A. Kostinski Apr 1996

Measurements Of The Complex Dielectric Constant Of Volcanic Ash From 4 To 19 Ghz, R. J. Adams, Warren F. Perger, William I. Rose, A. Kostinski

Department of Geological and Mining Engineering and Sciences Publications

Dielectric data in volcanic ash at weather radar wavelengths (centimeter range) are extremely sparse and are crucial for radar sensing of ash clouds and for imaging of volcanic terrains. This study extends previous data to include a wavelength range of 1.5–7.5 cm and volcanic ash compositions of 50–75% silica. The real part of the complex permittivity, ε′, of volcanic ash is 6 ± 0.5 (1σ) for all wavelengths. The imaginary part, ε″, ranges from 0.08 to 0.27. Both ε′ and ε″ show higher values at lower SiO2 concentration. It is safe to assume in any weather radar applications that the …


Method And Apparatus For Applying Herbicides, Marian Mazurkiewicz Jan 1996

Method And Apparatus For Applying Herbicides, Marian Mazurkiewicz

Mining Engineering Faculty Research & Creative Works

A method of applying herbicide to plants involves delivering a liquid herbicide solution to the plant foliage in a high pressure jet of sufficient energy to physically disrupt the surface of the foliage. The high pressure jet can be either a coherent jet or it can be a stream of droplets. The coherent stream can have sufficient energy to cut the foliage, creating new surfaces that are more wettable by the herbicide solution, and more susceptible to penetration by the herbicide in the solution. The droplets in the droplet stream can be made to be of sufficient size and energy …


Natural Zeolites For Pollution Control An Overview, M.M. Makweba Dec 1995

Natural Zeolites For Pollution Control An Overview, M.M. Makweba

Tanzania Journal of Science

Natural zeolites are minerals characterized by a framework of alumino-silicate whose structure contains channels occupied by water and exchangeable cations. The common known zeolites which occur in sedimentary rocks of volcanic origin include analcime, clinoptilolite, heulandite laumontite, philipsite, chabazite, erionite and mordenite. The zeolites have been studied in detail on their physical and chemical propertied. The ability of zeolite minerals like clinoptilolite to remove Cs-137 and Sr-90 from radioactive waste waters and to remove ammonium ions from municipal waste waters has been a milestone for zeolites to be applicable in pollution control. In Tanzania, zeolites occurrences have been reported in …


An Analysis Of The Use Of Programmable Controllers To Control An In Situ Leach Mine Wellfield, Jimmy W. Stokey Jan 1995

An Analysis Of The Use Of Programmable Controllers To Control An In Situ Leach Mine Wellfield, Jimmy W. Stokey

Dissertations and Theses @ UNI

In situ mining is a relatively new method that has the potential of recovering a variety of minerals. This process is quickly becoming an alternative to conventional mining techniques that are environmentally unsound. Two problems associated with in situ mining are, the amount of waste water generated by the process (bleed) and the uncontrolled migration of lixiviant outside the production zone (an excursion).

The purpose of this study was to determine if in situ mining processes could be monitored and controlled with a Sequential Control and Data Acquisition (SCADA) system. Using programmable logic controllers, a cost-effective SCADA system was designed …


Retrieval Of Sizes And Total Masses Of Particles In Volcanic Clouds Using Avhrr Bands 4 And 5, Shiming Wen, William I. Rose Mar 1994

Retrieval Of Sizes And Total Masses Of Particles In Volcanic Clouds Using Avhrr Bands 4 And 5, Shiming Wen, William I. Rose

Department of Geological and Mining Engineering and Sciences Publications

The advanced very high resolution radiometer (AVHRR) sensor on polar orbiting NOAA satellites can discriminate between volcanic clouds and meteorological clouds using two-band data in the thermal infrared. This paper is aimed at developing a retrieval of the particle sizes, optical depth, and total masses of particles from AVHRR two-band data of volcanic clouds. Radiative transfer calculations are used with a semi-transparent cloud model that is based on assumptions of spherical particle shape, a homogeneous underlying surface, and a simple thin cloud parallel to the surface. The model is applied to observed AVHRR data from a 13-hour old drifting cloud …


Longwall Electrical Control Issues: A Hazardous Waste Containment Application, D. Martinelli, R. S. Nutter Jr., R. Larry Grayson Jan 1994

Longwall Electrical Control Issues: A Hazardous Waste Containment Application, D. Martinelli, R. S. Nutter Jr., R. Larry Grayson

Mining Engineering Faculty Research & Creative Works

No abstract provided.


Method Of Stemming A Blast Hole, Paul Nicholas Worsey Oct 1993

Method Of Stemming A Blast Hole, Paul Nicholas Worsey

Mining Engineering Faculty Research & Creative Works

A method of stemming a blast hole loaded with an explosive charge. The blast hole has side walls, an outwardly opening mouth and a central axis extending longitudinally of the blast hole. The method comprises inserting a conduit having a discharge end inwardly through the mouth of the blast hole and positioning the discharge end of the conduit within the blast hole generally adjacent the explosive charge. Particulate stemming material is forced under pressure through the conduit for exit from its discharge end into the blast hole toward the explosive charge thereby to pack stemming material in the blast hole …


Surface Subsidence Over A Room-And-Pillar Mine In The Western United States, United States Department Of The Interior, Bureau Of Mines Jan 1993

Surface Subsidence Over A Room-And-Pillar Mine In The Western United States, United States Department Of The Interior, Bureau Of Mines

Mines and Mineral Resources

This report summarizes the results from the subsidence research study completed by the U.S. Bureau of Mines at the Roadside Mine, Powderhorn Coal Co., Palisade, CO. This research was conducted from February 1981 to August 1985, with additional data obtained during July 1991, to evaluate residual subsidence. The Bureau studied subsidence at three distinct room-and-pillar sections at separate locations over the mine and determined the maximum subsidence values and surface subsidence profiles for each mining section. Maximum subsidence of 3.0 ft. occurred over the room-and-pillar sections, with over-burden depths ranging from 50 to 600 ft. Surface tension cracks had occurred, …


Blast Plug And Stemming Construction For Blast Holes, Paul Nicholas Worsey Jan 1993

Blast Plug And Stemming Construction For Blast Holes, Paul Nicholas Worsey

Mining Engineering Faculty Research & Creative Works

A plug for use in stemming a blast hole having an explosive charge therein. The plug comprises a wedge member and a stabilizing structure on the wedge member. The wedge member tapers in an outward direction from a relatively wide base to a relatively narrow end and has a central axis extending endwise with respect to the wedge member. The stabilizing structure extends generally axially with respect to the wedge member from adjacent the base of the wedge member. The plug is to be positioned in the blast hole with the base of the wedge member facing inwardly toward the …


Dual Purpose Fuze, Paul Nicholas Worsey Jan 1993

Dual Purpose Fuze, Paul Nicholas Worsey

Mining Engineering Faculty Research & Creative Works

A dual purpose fuze for a projectile which can activate a quantity of material selected from a group including high explosive, low explosive, propellant and pyrotechnic compounds. The fuze includes a charge holder having a socket therein facing the quantity of material to be activated. A fuze charge located in the socket has a depression in it so formed as to cause the fuze charge to explode in a jet directed outwardly from the socket of sufficiently high energy to activate a high explosive in a high explosive projectile, the fuze charge being sufficiently small to prevent rupture of containment …


High Pressure Lubricooling Machining Of Metals, Marian Mazurkiewicz Jan 1992

High Pressure Lubricooling Machining Of Metals, Marian Mazurkiewicz

Mining Engineering Faculty Research & Creative Works

A method of machining metals, by effecting relative movement between a work piece and a tool having a cutting edge to cut the work piece and produce a chip, including injecting a high pressure jet of cooling liquid into the cutting zone during machining, the jet being at a pressure of at least about 5,000 p.s.i. The jet is preferably injected between the chip and the rake face of the cutting tool, and the trajectory of the jet is offset from the rake face of the cutting tool by a small amount and the jet is aimed at the cutting …