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Showing 1 to 20 of 23 for “"Mine Ventilation"”.
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Air leakage in underground mine ventilation
Air leakage in underground mines is the most common cause of inefficient distribution of ventilating air. Depending upon various factors, more than half of the fresh air entering a mine short-circuits to the return airways before reaching the working faces. Consequently, large leakages create an …
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Application of Background Oriented Schlieren (BOS) in Underground Mine Ventilation
… implications for analyzing underground mine ventilation systems. Currently, the widely utilized traditional schlieren methods are impractical underground due to complex equipment and design requirements. Background oriented schlieren (BOS) provides a solution to this problem. BOS …
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Optimization of control device locations and sizes in mine ventilation systems
… methodology for solving the semi-controlled ventilation network problem. After analysis and consideration of the objective and legal, technical and operation convenience factors, the semi-controlled network problem is formulated through a nonlinear nonconvex programming model. Using the …
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Development of new protocols to evaluate the transverse loading of mine ventilation stoppings
… based on rigid arching is proposed to determine the true transverse load capacity of stoppings. Arching is achieved by the restraint of the stopping against the mine roof and floor, whereby compressive forces are developed within the wall. A laboratory procedure using the NIOSH Mine Roof …
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A Method for Evaluating the Application of Variable Frequency Drives with Coal Mine Ventilation Fans
… method of controlling airflow for primary coal mine ventilation. With this method, the fan operates at a constant speed dictated by its motor design. The angles of the blades are adjusted to change the amount of airflow and pressure to meet ventilation requirements. Typically, the fan does not …
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Modelling of the ventilation system using ventsim considering the full mine mechanization drive at Konkola copper mines
Konkola Copper Mines Plc (KCM) is undergoing full mechanization drive aimed at increasing levels of production from the current 2.4 million tonnes to 7.5 million tonnes per annum. The mechanization of the mines will provide a large potential for reduced costs and improved profits, while at the same …
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A detailed justification for the selection of a novel mine tracer gas and development of protocols for GC-ECD analysis of SPME sampling in static and turbulent conditions for assessment of underground mine ventilation systems
… means of assessing air quantity in underground mine ventilation circuits. The execution of a tracer gas style ventilation survey allows for the direct measurement of air quantity in locations where this information is otherwise unattainable. Such instances include inaccessible regions of the …
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Development and Evaluation of a Permeation Plug Release Vessel (PPRV) for the Release of Perfluoromethylcyclohexane (PMCH) in Underground Mine Tracer Gas Studies
… (SF6) as a tracer gas for analyzing underground mine ventilation systems has been practiced for over 30 years. As a result, the methods used to release, sample, and analyze SF6 are well accepted. Although improvements are still being made to enhance the analysis of this tracer, the overall …
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Approaches to Simulation of an Underground Longwall Mine and Implications for Ventilation System Analysis
Carefully engineered mine ventilation is critical to the safe operation of underground longwall mines. Currently, there are several options for simulation of mine ventilation. This research was conducted to rapidly simulate an underground longwall mine, especially for the use of tracer gas in an …
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Determination of a novel mine tracer gas and development of a methodology for sampling and analysis of multiple mine tracer gases for characterization of ventilation systems
Ventilation in underground mines is vital to creating a safe working environment. Though there have been numerous improvements in mine ventilation, it is still difficult to ascertain data on the state of the ventilation system following a disaster in which ventilation controls have been potentially …
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An economic evaluation of backfilling in Virginia's coal mines
… waste dumps, improve coal recovery, and improve mine ventilation. However, backfilling is an additional operation in the coal mining cycle that can reduce productivity and increase production costs. This thesis identifies the backfilling methods applicable for coal mines in southwest Virginia. …
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Development of a remote analysis method for underground ventilation systems using tracer gas and CFD
Following an unexpected event in an underground mine, it is important to know the state of the mine immediately to manage the situation effectively. Particularly when part or the whole mine is inaccessible, remotely and quickly ascertaining the ventilation status is one of the pieces of essential …
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Towards Estimating Friction Factors of Mine Drifts from Low Density Point Clouds
… roughness for the purposes of underground mine ventilation planning is to choose values found in a variety of textbooks that attempt to match the excavation type. These values are then used in the Atkinson equation made popular in 1935 by McElroy to determine pressure drops and energy …
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Exploration of Respirable Dust Particles Sourced From Rock Strata in an Underground Coal Mine
… of regulatory standards for respirable coal mine dust (RCMD) concentration and crystalline silica content, and advancements in mine ventilation and dust controls led to a steady decline of occupational lung disease among US coal miners between the early 1970s and the mid-1990s. Since that …
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Evaluation and Design of Atmospheric Monitoring Interfaces and Approaches for Improved Health and Safety in Underground Coal Mines
A majority of underground coal mine disasters in the United States are due to explosions. Current atmospheric monitoring system (AMS) practices in the US could be enhanced to facilitate data sharing and learning of the entire work force. With the inclusion of additional atmospheric monitoring and …
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Utilization and Implementation of Atmospheric Monitoring Systems in United States Underground Coal Mines and Application of Risk Assessment
… as an extreme danger in underground coal mines and still occur despite significant technological advances. Mining researchers have been attempting to accurately measure and quantify ventilation and gas properties since early mining; however basic monitoring attempts were limited by the …
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Fire Simulation Cost Reduction for Improved Safety and Response for Underground Spaces
… strides have been made in the advancement of mine fire knowledge since the 1909 Cherry Mine Fire Disaster, one of the worst in U.S. history. However, fire hazards remain omnipresent in underground coal mines in the U.S. and around the world. A precise fire numerical analysis (simulation) …
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Flow characteristics of jet fans in mines: experimental and numerical modeling
The use of induction fans for face ventilation in room and pillar mines has proved to be an efficient, flexible, and viable technique. In addition to their merits over conventional systems, induction fans enable remote controlled mine operations with low maintenance requirements. Theoretical …
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Experimental and Theoretical Studies of Kinetics and Quality Parameters to Determine Spontaneous Combustion Propensity of U.S. Coals
… is one of the most serious problems to mine safety and production in the global coal industry. It is considered to be the trigger for fires and explosions in underground coal mines especially for gassy mines. Such thermal events are not easily detectable since they normally occur in …
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Design of an Experimental Mine Simulator for the Development of a Procedure for Utilization Multiple Tracer Gases in Underground Mines
An experimental mine simulator was constructed which will be used to conduct tracer gas experiments in the laboratory. The test apparatus simulates a mine in a tabular deposit and is modular and simple and can be easily rearranged to represent a variety of mine geometries. The apparatus is …
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