Vertical Stress And Stability Of Interburden Over An Abandoned Pillar Working Before Upward Mining: A Case Study,
2018
Taiyuan University of Technology
Vertical Stress And Stability Of Interburden Over An Abandoned Pillar Working Before Upward Mining: A Case Study, Jinwen Bai, Guorui Feng, Shanyong Wang, Tingye Qi, Jian Yang, Jun Guo, Zhen Li, Xianjie Du, Zehua Wang, Yunlou Du, Yujiang Zhang
Faculty & Staff Scholarship
Upward mining of the residual coal seam over an abandoned pillar working is one of the effective measures to alleviate the contradiction between limited resources and increased consumption. Interburden stability over an abandoned pillar working plays a significant role in guaranteeing the safety of upward mining; however, it has not yet been extensively studied and understood. In this study, the vertical stress of the interburden over an abandoned pillar working was first investigated. The mechanical model of the interburden was established and the damage conditions were analysed. Then, the stability of the interburden over 38502 abandoned workings in Baijiazhuang coal …
Analysis Of Monitored Ground Support And Rock Mass Response In A Longwall Tailgate Entry,
2018
NIOSH Pittsburgh Mining Research
Analysis Of Monitored Ground Support And Rock Mass Response In A Longwall Tailgate Entry, G.S. Esterhuizen, D.F. Gearhart, I.B. Tulu
Faculty & Staff Scholarship
A comprehensive monitoring program was conducted to measure the rock mass displacements, support response, and stress changes at a longwall tailgate entry in West Virginia. Monitoring was initiated a few days after development of the gateroad entries and continued during passage of the longwall panels on both sides of the entry. Monitoring included overcore stress measurements of the initial stress within the rock mass, changes in cable bolt loading, standing support pressure, roof deformation, rib deformation, stress changes in the coal pillar, and changes in the full three-dimensional stress tensor within the rock mass at six locations around the monitoring …
Deep Cover Bleeder Entry Performance And Support Loading: A Case Study,
2018
NIOSH
Deep Cover Bleeder Entry Performance And Support Loading: A Case Study, Ted M. Klemetti, Mark Alexander Van Dyke, Ihsan Berk Tulu
Faculty & Staff Scholarship
Several questions have emerged in relation to deep cover bleeder entry performance and support loading: how well do current modeling procedures calculate the rear abutment extent and loading? Does an improved understanding of the rear abutment extent warrant a change in standing support in bleeder entries? To help answer these questions and to determine the current utilization of standing support in bleeder entries, four bleeder entries at varying distances from the startup room were instrumented, observed, and numerically modeled. This paper details observations made by NIOSH researchers in the bleeder entries of a deep cover longwall panel—specifically data collected from …
Impact Of Nanobubbles On Mechanical Coal Flotation Process,
2018
Missouri University of Science and Technology
Impact Of Nanobubbles On Mechanical Coal Flotation Process, Ahmed Sobhy, Dongping Tao
Mining Engineering Faculty Research & Creative Works
A bank of three 10-liter mechanical flotation cells integrated with nanobubble technology was investigated to assess the impact of nanobubbles on coal separation performance at different operating variables. The most significant operation parameters such as fuel oil collector dosage, methyl isobutyl carbinol (MIBC) frother concentration, flow rate to nanobubble generator, feed solid concentration, and feed flow rate were studied individually. Nanobubbles are generated selectively on the hydrophobic particles, which should have a positive effect on flotation separation efficiency. It has been shown that frother concentration, collector dosage, and flow rate to nanobubble generator had a positive and significant effect on …
Computational Modeling Of Heat Transport And Volatile Extraction From Asteroid Materials,
2018
Missouri University of Science and Technology
Computational Modeling Of Heat Transport And Volatile Extraction From Asteroid Materials, Joel C. Sercel, Mark A. Crawford, Christopher Dreyer, Egboche Unobe, Robert Jedicke, Stanley Love, Leslie S. Gertsch
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
This paper presents the results of a program of computational modeling focused on elucidating the physics and chemical processes associated with the extraction of volatile materials from asteroid feedstocks with an eye toward use of the extracted materials for propulsion, radiation shielding, and replenishment of mission consumables. We present a math model of conductive heat transport, chemical processes, and gas escape by Darcian diffusion. Chemical processes in the model include pyrolysis of organic chemical constituents and thermal dehydration and decarbonization of hydrates and carbonates. The model is implemented in a spherical finite difference computational engine that predicts time histories of …
Dust Control Examination Using Computational Fluid Dynamics Modeling And Laboratory Testing Of Vortecone And Impingement Screen Filters,
2018
University of Kentucky
Dust Control Examination Using Computational Fluid Dynamics Modeling And Laboratory Testing Of Vortecone And Impingement Screen Filters, Ashish R. Kumar
Theses and Dissertations--Mining Engineering
Heavy industries, such as mining, generate dust in quantities that present an occupational health hazard. Prolonged exposure to the respirable dust has been found to result in many irreversible occupational ailments in thousands of miners. In underground mining applications, a variety of scrubbing systems are used to remove dust near the zones of generation. However, the wire-mesh type fibrous screens in the flooded-bed dust scrubbers used on continuous miners, are prone to clogging due to the accumulation of dust particles. This clogging results in a reduced capture efficiency and a higher exposure to the personnel. This research establishes the Vortecone, …
Calibration Of Mine Ventilation Network Models Using The Non-Linear Optimization Algorithm,
2018
Missouri University of Science and Technology
Calibration Of Mine Ventilation Network Models Using The Non-Linear Optimization Algorithm, Guang Xu, Jinxin Huang, Baisheng Nie, Duncan Chalmers, Zhuoming Yang
Mining Engineering Faculty Research & Creative Works
Effective ventilation planning is vital to underground mining. To ensure stable operation of the ventilation system and to avoid airflow disorder, mine ventilation network (MVN) models have been widely used in simulating and optimizing the mine ventilation system. However, one of the challenges for MVN model simulation is that the simulated airflow distribution results do not match the measured data. To solve this problem, a simple and effective calibration method is proposed based on the non-linear optimization algorithm. The calibrated model not only makes simulated airflow distribution results in accordance with the on-site measured data, but also controls the errors …
Assessment Of The Physical And Chemical Qualities Of Brine And The Application Of Nano Zerovalent Iron For The Treatment Of Brine Effluent,
2018
Missouri University of Science and Technology
Assessment Of The Physical And Chemical Qualities Of Brine And The Application Of Nano Zerovalent Iron For The Treatment Of Brine Effluent, M. J. Alegbe, O. S. Ayanda, P. Ndungu, O. O. Fatoba, A. Nechaev, L. F. Petrik
Mining Engineering Faculty Research & Creative Works
The arbitrary discharge of brine effluent from reverse osmosis treatment plants impacts negatively to the environment due to its high salinity. In the present study, brine effluent obtained from eMalahleni treatment plant, South Africa, was analyzed by pH, electrical conductivity and total dissolved solids measurements. The ion chromatography and the inductively coupled plasma optical emission spectroscopy were also used to examine the anion and cation content of the brine effluent. The analysis of major cations and anions indicated that the brine water quality was above the target water quality range for potable water. Geochemical modelling of the brine effluent classified …
A New Signal Processing Method For Acoustic Emission/Microseismic Data Analysis,
2018
Missouri University of Science and Technology
A New Signal Processing Method For Acoustic Emission/Microseismic Data Analysis, Charles Mborah
Doctoral Dissertations
"The acoustic emission/microseismic technique (AE/MS) has emerged as one of the most important techniques in recent decades and has found wide applications in different fields. Extraction of seismic event with precise timing is the first step and also the foundation for processing AE/MS signals. However, this process remains a challenging task for most AE/MS applications. The process has generally been performed by human analysts. However, manual processing is time consuming and subjective. These challenges continue to provide motivation for the search for new and innovative ways to improve the signal processing needs of the AE/MS technique. This research has developed …
Evaluation And Prevention Of Spontaneous Combustion During Handling And Storage Of Coal,
2018
University of Kentucky
Evaluation And Prevention Of Spontaneous Combustion During Handling And Storage Of Coal, Amir E. Najarzadeh
Theses and Dissertations--Mining Engineering
Spontaneous combustion of coal has historically been a major problem for the coal industry, predominantly during storage and transportation. Various methods have been used in the laboratory for evaluating the propensity of different coal sources to self-heat. However, the heterogeneity of coal and the complexity of the system has resulted in inconsistencies and sometimes conflicting results as indicated by the findings reported in several publications.
The primary objective of the current study was to build a laboratory scale apparatus that simulates the condition of a coal stockpile to evaluate the events leading to spontaneous combustion and develop potential remedies. As …
Investigation Of The Effectiveness Of An Integrated Flooded-Bed Dust Scrubber On A Longwall Shearer Through Laboratory Testing And Cfd Simulation,
2018
University of Kentucky
Investigation Of The Effectiveness Of An Integrated Flooded-Bed Dust Scrubber On A Longwall Shearer Through Laboratory Testing And Cfd Simulation, Sampurna N. Arya
Theses and Dissertations--Mining Engineering
Dust generation at an underground coal mine working face continues to be a health and safety issue. Prolonged exposure to high concentrations of airborne respirable dust can cause a debilitating and often fatal respiratory disease called Black Lung. In addition, the deposition of float dust in mine return airways poses a serious safety hazard if not sufficiently diluted with inert rock dust. A localized methane explosion can transition into a self-propagating dust explosion. Since dust is a byproduct of various mining activities, such as cutting and loading, crushing, and transportation, the dust-related issues cannot be totally eliminated. However, the adverse …
Investigation Of Environmental Cadmium Sources In Eastern Kentucky,
2018
University of Kentucky
Investigation Of Environmental Cadmium Sources In Eastern Kentucky, Elizabeth Maher
Theses and Dissertations--Mining Engineering
Utilizing data collected by the University of Kentucky Lung Cancer Research Initiative (LCRI), this study investigated potential mining-related sources for the elevated levels of cadmium in Harlan and Letcher counties. Statistical analyses for this study were conducted utilizing SAS. A number of linear regression models and logarithmic models were used to evaluate the significance of the data. The linear regression models consisted of both simple and multivariate types, with the simple models seeking to establish significance between the potential sources and urine cadmium levels and the multivariate models seeking both to identify any statistically significant linear relationships between source types …
Numerical Analysis Of Stress Distributions For Multiple Backfilled Stopes,
2018
University of Kentucky
Numerical Analysis Of Stress Distributions For Multiple Backfilled Stopes, Christopher Richard Newman
Theses and Dissertations--Mining Engineering
Over the past three decades, technological innovations with respect to cemented paste backfill (CPB) as a means of ground support has allowed for increased production within the mining industry, management mine waste costs, as well as the improvement of the overall health and safety of underground mining operations. Despite the extensive use of this relatively new ground support material, many fundamental factors affecting the design of safe and economical CPB structures are still not well understood.Recently, a significant amount of academic and industry research has been conducted to better understanding the distribution of stress with respect to primary-secondary extraction sequencing …
Analysis Of Underground Coal Mine Structures Subjected To Dynamic Events,
2018
University of Kentucky
Analysis Of Underground Coal Mine Structures Subjected To Dynamic Events, Brooklynn Yonts
Theses and Dissertations--Mining Engineering
Underground coal mine explosions pose a significant threat to infrastructure such as mine seals and refuge alternative chambers. After a mine seal failed in the Sago mine disaster, which took the life of 12 miners, design requirements were reexamined and improved. However, most research being completed on the analysis of mine structures during an explosive event focuses solely on peak pressure values, while ignoring the impact of pressure duration. This study investigates the impact pressure duration, waveform shape, and impulse have on structural displacement, while also exploring what pressures and duration can be expected during a mine explosion. Additionally, the …
Synthesis Of Single-Hole Vibration Waveforms From A Mining Blast,
2018
University of Kentucky
Synthesis Of Single-Hole Vibration Waveforms From A Mining Blast, Lifeng Li
Theses and Dissertations--Mining Engineering
In mining engineering, blast-induced ground vibration has become one of the major concerns when production blasts are conducted, especially when the mining areas and the blast sites are near inhabited areas or infrastructure of interest. To comply with regulations, a vibration monitoring program should be developed for each mining operation. The vibration level, which is usually indicated by the peak particle velocity (PPV) of the vibration waveform, should fall below the maximum allowable values. Ideally, when blasting is near structures of interest (power towers, dams, houses, etc.), the vibration level (PPV) should be predicted prior to the actual production blasts. …
Effectiveness Of Ammonium Ion In Low Salinity Waterflooding In Shaly-Sandstone Reservoir,
2018
Faculty of Engineering
Effectiveness Of Ammonium Ion In Low Salinity Waterflooding In Shaly-Sandstone Reservoir, Hung Vu Quoc
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this study was presented the pre-feasibility study of silica sand processing plant in Sihanoukville province. The resources approximately 8,750,000 tons, would be a high potential deposit for the glass industry. In this study focuses on the characteristics of the silica sand, methodology to remove the impurities which contained high Fe2O3, Al2O3 and another major oxide element, and economic evaluation technique. To identification of silica sand which used sieve analysis, Frantz isodynamic magnetic separator following by electrical microscope, XRD, and XRF. Therefore, to upgrade the quality of silica sand, which is using Shaking Table, Wet High-Intensity Magnetic Separator, and Reverse …
Management Of Coal Dust Explosions In United States' Coal Mines Using Bag Type Passive Explosion Barriers,
2018
Missouri University of Science and Technology
Management Of Coal Dust Explosions In United States' Coal Mines Using Bag Type Passive Explosion Barriers, Jay Robert Schafler
Masters Theses
"The most significant and powerful hazard that exists in an underground coal mine is a coal dust explosion. A coal dust explosion has the potential to propagate throughout a mine resulting in massive damage to the mine and equipment, as well as tragic loss of life. An assessment of current global regulations and practices uncovered four main control methods utilized to prevent coal dust explosions in coal mines world-wide. The United States is one of the few countries that does not regulate or employ all four of these safety practices. Additionally, a review of past research into coal dust explosions …
Improving Workers' Safety And Health In The Zimbabwean Mining And Quarrying Industry,
2018
Walden University
Improving Workers' Safety And Health In The Zimbabwean Mining And Quarrying Industry, Bernard Mabika
Walden Dissertations and Doctoral Studies
Lack of effective occupational safety and health (OSH) strategies is a reason that
workplace accidents in the mining and quarrying industry remain high, making the
industry one of the riskiest operations worldwide. The purpose of this multiple case study
was to explore successful strategies mining and quarrying leaders in Zimbabwe used to
improve OSH. The key research question addressed successful strategies leaders in the
mining and quarrying industry use to improve employee occupational safety and health in
Zimbabwe. Six successful business leaders from 3 mining and quarrying mines in
Zimbabwe demonstrated an exception to unsafe practices, particularly through their
exceptional …
Ore Reserves Estimation Of The Nam Nga Coal Deposit, Lao Pdr, Using Geostatistical Method,
2018
Faculty of Engineering
Ore Reserves Estimation Of The Nam Nga Coal Deposit, Lao Pdr, Using Geostatistical Method, Tongvang Bliachongvang
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research study focuses on estimating the coal deposit quantity and qualities as CV and AC at Nam Nga coal deposit, Lao PDR using OK and SGS geostatistical methods. A total of 295 assays data from 51 exploration drill holes collected from LID Company were used. The results reveal that OK produces geological resource of 2.2 MT with an average CV of 3,733 kcal/kg and an average AC of 48.68 %. The mineable reserve computed from OK's ultimate pit design and pit adjustment are 0.55 MT. The OK method produces 9.32 MT of wastes, yielding a stripping ratio of 10.4:1. …
The Effect Of Overloading On Reliability Of Wheel Loader Structural Components,
2018
Missouri University of Science and Technology
The Effect Of Overloading On Reliability Of Wheel Loader Structural Components, Eric Raymond Achelpohl
Doctoral Dissertations
"This research attempts to provide a fundamental understanding into the relationship between the productivity of material handling equipment, specifically wheel loaders, and their ability to operate reliably when subjected to high overload conditions. The overall aim is to determine the effect of overloading the bucket on wheel loader reliability. The specific objectives of the research are to: 1) evaluate the effect of overloading the bucket on wheel loader productivity; 2) examine the effect of overloading the bucket on hydraulic pressures in the hoist cylinders (used as a proxy for forces on a wheel loader); and 3) investigate the effect of …
