Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Engineering

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 38371 - 38400 of 41102

Full-Text Articles in Entire DC Network

Evaluation Of Discriminating Fire Sensors In Two Underground Coal Mines, William J. Francart Jun 1999

Evaluation Of Discriminating Fire Sensors In Two Underground Coal Mines, William J. Francart

U.S. Mine Ventilation Symposium

Fire detection in underground coal mines using carbon monoxide (CO) based monitoring systems has been very effective in many mines. Many systems have been able to detect fires in early stages of development at very low CO levels. However in mines which use extensive diesel haulage and support vehicles, the systems have been less sensitive to early detection due to diesel exhaust contaminants elevating baseline CO levels. A new technology has been tested in two underground coal mines which is designed to discriminate between the CO produced by diesel engines and CO from a fire by correcting the CO concentration …

Go to article

Cfd Applications In Tunnel Ventilation Analysis, Richard E. Ray Jr., Abdelgbani Zigh Jun 1999

Cfd Applications In Tunnel Ventilation Analysis, Richard E. Ray Jr., Abdelgbani Zigh

U.S. Mine Ventilation Symposium

Longitudinal ventilation systems in transit and rail tunnels are typically analyzed by one dimensional ventilation network simulation models, such as the Subway Environment Simulation (SES) program. However, in recent years computational fluid dynamics (CFD) modeling has been utilized in conjunction with one-dimensional ventilation network programs to study ventilation systems for large volume spaces such as transit stations and rail overbuilds, as well as for vehicular tunnels. CFD uses numerical methods to simulate complex fluid flow phenomena in three dimensions to predict the distribution of velocity, pressure, temperature, concentration, and other relevant variables throughout the volume. This paper presents an overview …

Go to article

Novel Approach To The Energy Analysis Of Mine Cooling Strategies, C. T. Twort, I. S. Lowndes, S. J. Pickering Jun 1999

Novel Approach To The Energy Analysis Of Mine Cooling Strategies, C. T. Twort, I. S. Lowndes, S. J. Pickering

U.S. Mine Ventilation Symposium

The extraction of minerals and coal at increasing depth, employing higher-powered, mechanized machinery to increase production levels imposes an increased burden on the ability to maintain an acceptable mine climate. Any deterioration in the mine climate within working zones may adversely affect the health and safety of the workforce. The combination of the optimal design of the mine system layout, together with the selective application of suitable ventilation and cooling systems, may be used to control the climate within working zones. The adoption of mechanical cooling within mines is an expensive process in terms of both capital and operating costs. …

Go to article

Three Underground Coal Mine Explosions — Twenty Miners Killed — One Reason, Andrzej M. Wala, Jason R. Stoltz Jun 1999

Three Underground Coal Mine Explosions — Twenty Miners Killed — One Reason, Andrzej M. Wala, Jason R. Stoltz

U.S. Mine Ventilation Symposium

Three mine explosions which occurred in the 1980s (1983 - McClure No. 1 Mine, Virginia; 1984 - Greenwich Collieries No. 1 Mine, Pennsylvania; and 1989- Pyro No.9 Slope Williams Station Mine, Kentucky) cost twenty lives. The authors, by investigating these three cases, found a common ventilation problem. This problem was the misunderstanding of the diagonal connections in the mine ventilation system (MVS). Based on the findings from these investigations, the authors explain the importance of diagonal connections in a MVS and discuss other factors that affected safety.

Go to article

Proposed Regulation On Diesel Particulate Matter In Underground Coal Mines, Thomas F. Tomb Jun 1999

Proposed Regulation On Diesel Particulate Matter In Underground Coal Mines, Thomas F. Tomb

U.S. Mine Ventilation Symposium

The Mine Safety and Health Administration published a proposed rule for underground coal mines that use diesel-powered equipment. The proposed rule, published April 9, 1998, would establish new health standards. These new standards would reduce the risks to miners of serious health hazards that are associated with exposure to high concentrations of diesel particulate matter (dpm). The proposed rule would require that mine operators install and maintain high efficiency filtration systems on the most polluting types of diesel-powered equipment. The rule would also require that miners be trained about the hazards of dpm exposure. This paper reviews the requirements of …

Go to article

Mine Fire Detection In The Presence Of Diesel Emissions, J. C. Edwards, R. A. Franks, G. F. Friel, C. P. Lazzara, J. J. Opferman Jun 1999

Mine Fire Detection In The Presence Of Diesel Emissions, J. C. Edwards, R. A. Franks, G. F. Friel, C. P. Lazzara, J. J. Opferman

U.S. Mine Ventilation Symposium

A series of four coal combustion experiments was conducted at the National Institute for Occupational Safety and Health's (NIOSH) Pittsburgh Research Laboratory (PRL) in the Safety Research Coal Mine (SRCM) to evaluate the response of fire sensors to a small 0.61 m square smoldering coal fire which transitions to flaming combustion in the presence of diesel emissions. An optical path smoke sensor alarmed earlier than a point type diffusion mode ionization smoke sensor, which alarmed prior to a co alert value of 5 PPM above ambient. The presence of steady state diesel emissions resulted in a decrease in the optical …

Go to article

Committees, Multiple Members Jun 1999

Committees, Multiple Members

U.S. Mine Ventilation Symposium

No abstract provided.

Go to article

Cfd Analysis Of Mine Fire Smoke Spread And Reverse Flow Conditions, J. C. Edwards, C. C. Hwang Jun 1999

Cfd Analysis Of Mine Fire Smoke Spread And Reverse Flow Conditions, J. C. Edwards, C. C. Hwang

U.S. Mine Ventilation Symposium

A Computational Fluid Dynamics (CFD) program was used to model buoyancy induced Product-Of-Combustion (POC) spread from experimental fires in the National Institute For Occupational Safety And Health (NIOSH), Pittsburgh Research Laboratory (PRL), safety research coal mine. In one application, the CFD program was used to predict spread from fires in an entry under zero airflow conditions. At a location, 0.41 m below the entry's roof at a distance of 30 m from the fire, the measured smoke spread rates were 0.093 and 0.23 m/s for a 30 and a 296 kw fire, respectively. The CFD program predicted spread rates of …

Go to article

Installation Of Two Main Fans At P.T. Freeport Indonesia's Underground Facilities, Felipe Calizaya, A. Mulyadi Jun 1999

Installation Of Two Main Fans At P.T. Freeport Indonesia's Underground Facilities, Felipe Calizaya, A. Mulyadi

U.S. Mine Ventilation Symposium

This study summarizes the technical aspects related to the installation of two main fans at P.T. Freeport Indonesia: one centrifugal and one axial. The fans were installed to increase the exhaust capacity of two vent systems. The 450 kW fan has been installed on surface to support an underground mine expansion project. The installation included the construction of a transition chamber, a retention wall, and the fan installation and commissioning. The 250 kW fan has been installed in an incline to increase the exhaust capacity of an ore pass ventilation system. The study presents the installation details from ground excavation …

Go to article

Axial Flow Fan Use At San Manuel Mine, Kuda R. Mutama, Dave P. Pelletier Jun 1999

Axial Flow Fan Use At San Manuel Mine, Kuda R. Mutama, Dave P. Pelletier

U.S. Mine Ventilation Symposium

A case study is presented for the use of multiple axial flow main fans as the principle source of the primary mine ventilation system for a large multi level mine. Formerly owned by Magma Copper, BHP Copper Inc.'s San Manuel Mine is a large underground block caving copper mine which started producing copper in 1955. The San Manuel Mine produces over 50,000 tons per day sulfide copper ore. The total airflow into this mine is approximately 800 m3/s (1,600,000 cfm). Providing adequate ventilation has been a very challenging experience as new, deeper levels are developed. BHP relies on …

Go to article

Increasing Energy Efficiency Of Mine Ventilation Systems, Riyaz Papar, Andrew Szady, William D. Huffer, Vern Martin, Aimee Mckane Jun 1999

Increasing Energy Efficiency Of Mine Ventilation Systems, Riyaz Papar, Andrew Szady, William D. Huffer, Vern Martin, Aimee Mckane

U.S. Mine Ventilation Symposium

Every year the United States mining industry spends millions of dollars on underground ventilation systems. In the U.S., fan systems used for mine ventilation consume approximately 12,000 million kWh annually (Xenergy, 1997, 1998). Potential motor-driven system energy savings can be realized by using mature, proven, and cost-effective technologies. Such saving potentials exist in the mining industry and the U.S. Department of Energy's Motor Challenge program aims to assist the industry in capturing them. Energy efficiency upgrades can also achieve significant non-energy benefits such as better equipment reliability, longer equipment life, reduction in maintenance costs and downtime, and an improved working …

Go to article

Ventilation Network Optimization For Deep Mines, Ventzislav Bojilov, Mitko Hadjiev, Georgi Shoushoulov Jun 1999

Ventilation Network Optimization For Deep Mines, Ventzislav Bojilov, Mitko Hadjiev, Georgi Shoushoulov

U.S. Mine Ventilation Symposium

The development of underground mines in Bulgaria has reached depth limit. The conventional approach for engineering the mine ventilation is unsatisfactory under the existing level of concentration and intensification of mining work under the already complicated mining and geological conditions. This necessitates the optimization of ventilation networks for achieving the required efficiency and reliability. Direct measurements in mines has created an adequate numerical mine ventilation model. This model can optimize and forecast the future development of the mine ventilation system with the help of computer software. By means of the prepared nomograms the individual parameters of the ventilating flow are …

Go to article

An Integrated Strategy For Emergency Egress From An Underground Metal Mine, Rick Brake Jun 1999

An Integrated Strategy For Emergency Egress From An Underground Metal Mine, Rick Brake

U.S. Mine Ventilation Symposium

The fact that major fires are rare events in underground metal mines means there is often little on-site experience in dealing with these situations. Elaborate strategies that rely on a high degree of training at all levels to be effective are likely to fail, especially with the trend in Australia towards smaller mines and "fly in-fly out" operations. A robust strategy is required. The key items in such a strategy are: early detection and warning of personnel, personal belt-worn oxygen-generating self-rescuers, high integrity escape routes and self-contained refuge stations, simple procedures, reliable personnel ''tagging" systems and sufficient, trained, search and …

Go to article

Deployment Of Self-Contained Self Rescuers In Australian Coal Mines, Najdat I. Aziz, Ernest Y. Baafi, Paul Mackenzie-Wood Jun 1999

Deployment Of Self-Contained Self Rescuers In Australian Coal Mines, Najdat I. Aziz, Ernest Y. Baafi, Paul Mackenzie-Wood

U.S. Mine Ventilation Symposium

In view of the recent mine disasters in the Australian coal mines, there has been a need to develop strategies to introduce SCSRs into coal mines to replace the approved filter self rescuers. A study was undertaken to evaluate the performances of the units in the normal Australian underground coal mine conditions. The study involved a laboratory and field trials at four underground coal mines using a total of 37 volunteers. These volunteers walked along the escape route at their respective mines on the first day carrying the SCSRs on their belts. The walk was repeated on a second day …

Go to article

Controlled Recirculation In Deep South African Gold Mines, Mark Butterworth Jun 1999

Controlled Recirculation In Deep South African Gold Mines, Mark Butterworth

U.S. Mine Ventilation Symposium

Despite the many advantages and potential benefits of using controlled recirculation in Deep South African gold mines the strategy has found little favour. Indeed, controlled recirculation of air is at present rarely considered as an option in the planning and implementation of these underground ventilation systems. This paper broadly examines controlled recirculation, the benefits and advantages that could accrue from its use, reasons that may detract from its use and some solutions for addressing shortcomings. A brief historical review of controlled recirculation in the context of the South African gold mining industry is given. The advantages, which could result from …

Go to article

Ventilating The Box Cut Of A Two-Pass 40-Ft Extended Cut, Edward D. Thimons, Charles D. Taylor, Jeanne A. Zimmer Jun 1999

Ventilating The Box Cut Of A Two-Pass 40-Ft Extended Cut, Edward D. Thimons, Charles D. Taylor, Jeanne A. Zimmer

U.S. Mine Ventilation Symposium

On a continuous miner coal face methane concentrations are affected by the quantity of fresh intake air reaching the face. When mining the box cut on a 12.2-m (40-ft) two-pass extended cut face, the continuous miner is always at the point of deepest penetration, and operation of the machine-mounted dust scrubber and water spray system improve the flow of fresh air to the end of the box cut. However, when the continuous miner leaves the box cut to begin cutting the 40-ft slab, little is known about how much ventilation air reaches the end of the box cut. The Pittsburgh …

Go to article

Control Of Silica Dust In Slate Milling Operations, Karl T. Ahlen, Robert A. Haney, Joseph M. Denk Jun 1999

Control Of Silica Dust In Slate Milling Operations, Karl T. Ahlen, Robert A. Haney, Joseph M. Denk

U.S. Mine Ventilation Symposium

The Mine Safety and Health Administration (MSHA) conducted a study to assess the present state of technology used for controlling employees' respirable silica-bearing dust exposures during dimension slate milling operations. For this study, twelve slate milling operations were visited and various measurements were taken and observations made. These measurements and observations included exhaust and room airflow, types of enclosures, water usage, and building volumes for each of the milling processes. These mills usually employed between five and twenty people. From the study, general guidelines were developed from the best practices observed and can be used at the various sawing, splitting, …

Go to article

Measurements Of Dust Extraction Effectiveness On A Testing Stand, Walenty Frydel, Marcin Steindor Jun 1999

Measurements Of Dust Extraction Effectiveness On A Testing Stand, Walenty Frydel, Marcin Steindor

U.S. Mine Ventilation Symposium

The stand is used to determine characteristics of fans and dust collectors, especially their efficiency at different levels of dustiness of the air being cleaned. Both wet- and dry-dust collectors arc manufactured as experimental installations, prototypes products designed for industrial applications. The design of the research installation has been so elaborated that the installation is characterized by great flexibility in respect of its applicability, enabling both comparison tests and attestation tests to be carried out. The accepted programme of the basic research covers testing of dust collectors of vortex type equipped with rotors featuring axial, diagonal and radial flow as …

Go to article

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 …

Go to article

The Influence Of Coal Physical And Mechanical Properties And Mining Energy Consumption Factor On Airborne Respirable Dust Level, Antoni Koziel, Malgorzata Malec, Ewa Wardas Jun 1999

The Influence Of Coal Physical And Mechanical Properties And Mining Energy Consumption Factor On Airborne Respirable Dust Level, Antoni Koziel, Malgorzata Malec, Ewa Wardas

U.S. Mine Ventilation Symposium

The fact that there are not any explicitly defined relationships describing the influence of physical and mechanical properties of coal and of energy consumption factor on dust level prompted Polish and American investigators to carry out a joint research project within the framework of the U.S.- Poland Maria Sklodowska-Curie Joint Fund II. The paper presents methods used to perform tests under laboratory conditions at the Pittsburgh Research Laboratory as well as under real conditions in the course of coal cutting in polish coal mines. Measuring systems and results of the tests are described. The analysis carried out has provided a …

Go to article

Considerations For Estimating Remote Operator Dust Exposure Using Fixed-Point Samples On Continuous Mining Sections, Jeffrey M. Listak, Gerrit V. R. Goodman, Robert A. Jankowski Jun 1999

Considerations For Estimating Remote Operator Dust Exposure Using Fixed-Point Samples On Continuous Mining Sections, Jeffrey M. Listak, Gerrit V. R. Goodman, Robert A. Jankowski

U.S. Mine Ventilation Symposium

Respirable dust studies were conducted at several underground coal mining operations to evaluate and compare the dust measurements of fixed-point machine-mounted samples on a continuous miner and personal samples of the remote miner operator. Fixed-point sampling was conducted at the right rear corner of the continuous miner which corresponded to the traditional location of the operator's cab. Although it has been documented that higher concentrations of dust are present at the machine-mounted position, this work sought to determined whether a relationship exists between the concentrations at the fixed-point position and the dust levels experienced at the remote operator position and …

Go to article

Laboratory Evaluation Of Pressure Differential Based Respirable Dust Detector Tube, Jon C. Volkwein, April L. Schoeneman, Steven J. Page Jun 1999

Laboratory Evaluation Of Pressure Differential Based Respirable Dust Detector Tube, Jon C. Volkwein, April L. Schoeneman, Steven J. Page

U.S. Mine Ventilation Symposium

A new type of respirable dust sampler was developed and compared side by side to personal gravimetric samplers in the laboratory. The new sampler correlates filter back pressure with mass accumulation to provide mid-shift and end-of-shift determinations of cumulative exposure. The sampler uses a small low flow rate pump to draw dust through a small detector tube that contains a porous urethane foam respirable classification section and glass fiber filter that collects respirable dust. Six different coal dusts were aerosolized in a laboratory dust chamber and a total of 118 triplicate observations were obtained. For individual coal types, the correlation …

Go to article

The Effects Of A Diesel Particulate Filter And Fuel Borne Catalyst On Engine Emissions, Mahé Gangal, Thierry Leprince, John Muter, Brent Rubeli Jun 1999

The Effects Of A Diesel Particulate Filter And Fuel Borne Catalyst On Engine Emissions, Mahé Gangal, Thierry Leprince, John Muter, Brent Rubeli

U.S. Mine Ventilation Symposium

CANMET has been involved in an industry-government program to assess the quality of mine air and to improve the working environment. One aspect of the program is to reduce diesel particulate matter (DPM) generated by heavy-duty diesel vehicles having low exhaust temperature duty cycles. The low exhaust gas temperatures that are common in modem engines lead to insufficient regeneration of diesel particulate filters (DPF). A study was undertaken in partnership with DCL International to examine additive assisted regeneration. This study uses a cerium based fuel-borne catalyst to complete the regeneration of a DPF. Regeneration of a DPF occurs when the …

Go to article

The State Of Mining Research In Niosh, R. Larry Grayson Jun 1999

The State Of Mining Research In Niosh, R. Larry Grayson

U.S. Mine Ventilation Symposium

No abstract provided.

Go to article

Management Of Mine Explosion Risks, Jan J. L. Du Plessis, J. W. Oberholzer Jun 1999

Management Of Mine Explosion Risks, Jan J. L. Du Plessis, J. W. Oberholzer

U.S. Mine Ventilation Symposium

The management of explosions in the underground mining environment has been a high priority for managers since the turn of the century. In the early 1900s explosions, worldwide, reached catastrophic dimensions. In a number of large explosions more than 1000 people have died. In the early years of research, the basics of why explosions occurred were investigated and the participation of coal dust in underground coal mine explosions was proved. Taffanel, a French researcher, was one of the pioneers in establishing the use of stone dust and was instrumental in the design and development of the first stone-dust barriers. Throughout …

Go to article

Environ 2.5 — A Mine Ventilation And Cooling Network Simulation Tool, W. M. Marx Jun 1999

Environ 2.5 — A Mine Ventilation And Cooling Network Simulation Tool, W. M. Marx

U.S. Mine Ventilation Symposium

As mining operations progress, ore reserves are depleted and alternative are almost invariably found at increasing depth and a host of attendant difficulties in this regard face· the mine operator. Most significant among these is the control of the increasingly hostile environment encountered at depth in terms of both ground behaviour and the increasing hot environment. To enable the practical and economical design of mine ventilation and cooling systems, ventilation practitioners need effective and efficient tools to perform their duty. One such tool is the Environ 2.5, an interactive network simulation program that allows for the simultaneous simulation of airflow …

Go to article

Msha Approval Process, David C. Chirdon Jun 1999

Msha Approval Process, David C. Chirdon

U.S. Mine Ventilation Symposium

The hazardous nature of the underground mining environment necessitates the use of equipment and mining products designed to ensure safe usage in this hostile environment. Title 30, code of federal regulations (30 CFR) includes requirements that all equipment and products intended for use in potentially gassy areas of underground mines be approved by the mine safety and health administration (MSHA). Design and performance requirements for many of the products intended for use in the underground environment are also part of 30 CFR. This paper describes the processes available to potential applicants for obtaining MSHA approval. Emphasis is placed on ventilation-related …

Go to article

Ventilation Optimization — Balancing The Need For More Power Against Environmental Concerns, Stephen G. Hardcastle, R. D. Lamond, D. T. Willoughby Jun 1999

Ventilation Optimization — Balancing The Need For More Power Against Environmental Concerns, Stephen G. Hardcastle, R. D. Lamond, D. T. Willoughby

U.S. Mine Ventilation Symposium

This paper shows how the Nanisivik mine was able to improve the underground working environment, decrease operational costs, and reduce its impact on the environment through optimizing their ventilation system. Through re-organizing their ventilation system, the overall flow through the mine increased by at least 20%, and local flows increased by over 100%. This change also resulted in a 45% reduction of fan motor power. And as a consequence of reduced power demands the mine has decreased its Green-house gas (GHG) emissions. Currently, ventilation is typically responsible for 40% of a Canadian mine's underground electrical consumption. This could dramatically change …

Go to article

Mine Safety In Chinese Coal Mines: Today And Tomorrow, Xintan Chang, Yunxiu Sai Jun 1999

Mine Safety In Chinese Coal Mines: Today And Tomorrow, Xintan Chang, Yunxiu Sai

U.S. Mine Ventilation Symposium

As a result of governmental agency restructuring, China's coal industry has been going through evolutionary changes as well in recent years. This paper discusses the various structural changes within the former Ministry of Coal Industry (MOCI) that occurred recently and its impact on coal production, health and safety regulation enforcement, safety training, and higher education.

Go to article

Modelling Of The Occurrence Of Hydrogen Sulphide In Coal Seams, A. D. Stewart Gillies, Mehmet S. Kizil, Hsin Wei Wu, Timothy J. M. Harvey Jun 1999

Modelling Of The Occurrence Of Hydrogen Sulphide In Coal Seams, A. D. Stewart Gillies, Mehmet S. Kizil, Hsin Wei Wu, Timothy J. M. Harvey

U.S. Mine Ventilation Symposium

Hydrogen Sulphide (H2S) has been encountered within a number of Bowen Basin collieries, Central Queensland, Australia. High concentration occurrence during mining of a longwall panel raises a number of potential problems, which demand greater understanding to allow efficient mining while maintaining safe and healthy environmental conditions. Longwall panels at Mine A and Mine B have recently mined through H2S zones. The high H2S zone mined through at Mine A was wide and covering the whole length of the face comparing to the narrow H2S zone which was cutting the panel at 45° …

Go to article

First Prev Next Last