Engineering Commons^™

Discrete Element Modeling To Predict Muckpile Profiles From Cast Blasting, Russell Lamont

Theses and Dissertations--Mining Engineering

Movement of overburden or ore from one location to another may be considered the primary physical process of mining. The means by which it is transported is then of primary concern both to economic production and cost control. The geologic characteristics of some mineral deposits, especially coal and phosphates, lend themselves to overburden transport by means of cast blasting, which when efficiently designed has proven itself to be a cheaper method than traditional truck/shovel, dragline, or even dozer push transport. Simultaneously, this movement of a significant portion of overburden using explosives may enable an operation to increase mineral production, as …

The Methodology For Integrating Robotic Systems In Undeground Mining Machines, Peter Kolapo

Theses and Dissertations--Mining Engineering

Roof bolting is a critical operation in ensuring the safety and stability of underground mines by securing the roof strata with bolts. The process involves moving and manipulating heavy tools while being vigilant about the safety of the area. During the installation of roof bolts, operators are exposed to hazardous conditions due to challenging working conditions in underground mines, extensive working hours, and demanding shift schedules leading to personnel fatigue and influencing operators to take shortcuts that may increase the risk of injuries and fatal accidents. The successful completion of roof bolting tasks depends heavily on operator judgment and experience …

Prediction Of Blast-Induced Ground Vibrations: A Comparison Between Empirical And Artificial-Neural-Network Approaches, Luis F. Velasquez

Theses and Dissertations--Mining Engineering

Ground vibrations are a critical factor in the rock blasting process. The instantaneous load application exerted by the gas pressure during the detonation process acts on the blasthole walls creating dynamic stresses in the adjacent rock. This triggers different sorts of stress waves, mainly divided into two categories: body and surface waves. The first comprises the P and the S waves, while the second comprises Rayleigh waves. These waves spread concentrically starting at the blast location and move along the ground surface and its interior, being attenuated as they reach further distances.

In most cases, and accepting the hypothesis that …

Recovery Of Valuable Metals From Electronic Waste Using A Novel Ammonia-Based Hydrometallurgical Process, Peijia Lin

Theses and Dissertations--Mining Engineering

The growing quantity of waste electrical and electronic equipment (WEEE), also known as electronic waste (E-waste), has been an area of growing public concern. The abundance of valuable metals contained in waste printed circuit boards (WPCBs) has made it a promising secondary resource, especially for Cu and Au. Although the recovery of metals from WPCBs via hydrometallurgical routes has been studied extensively over the past 20 years, most of the research has been limited in the laboratory. In current hydrometallurgical processes, strong acids and expensive oxidizers are often used to ensure a high recovery of metals without considering the sustainability …

Prediction Of Dynamic Subsidence In The Proximity Of Longwall Panel Boundaries, Jesus David Romero Benitez

Theses and Dissertations--Mining Engineering

The development of mining subsidence has a dynamic character, and it is related to the mining rate and a time coefficient. Reliable prediction of dynamic deformations is important when planning to undermine important structures that cannot account for large relative deformations and or large horizontal strains. This thesis discusses subsidence development for a number of points over a retreating longwall panel in the eastern US. The prediction points are at different distances from the excavation rib and, therefore, present a different response in terms of dynamic movements. Final movements, i.e., measurements after the panel was fully extracted, were used to …

An Acid Baking Approach To Enhance Rare Earth Element Recovery From Bituminous Coal Sources, Ahmad Nawab

Theses and Dissertations--Mining Engineering

Rare earth elements (REE) are a group of 17 elements typically classified as light and heavy rare earth elements, which play a crucial role in developing the latest technologies for energy, defense, and medical sectors. Even though REEs have been found in more than 200 minerals, only bastnaesite, monazite and xenotime are commercially exploited for REE extraction. However, the recent exponential increase in REE demand has spurred countries such as the United States into research for the extraction of REEs from secondary sources such as coal, acid mine drainage, and coal ash. Several coal sources (e.g., Fire Clay seam coal) …

A Laboratory And Numerical Investigation Of The Strength Of Irregularly Shaped Pillars, Zachary Wedding

Theses and Dissertations--Mining Engineering

Underground mining operations utilize the room-and-pillar mining method that extracts the orebody and creates ‘rooms’ and leaves the remaining in-situ material as ‘pillars’ to support the overburden. Room-and-pillar mines are traditionally designed in square or rectangular-shaped pillars. This work presents laboratory experiments testing the compressive strengths of specimens modeled after square and parallelogram-shaped pillars and numerical models of square and -parallelogram-shaped pillar systems. The uniaxial compressive strength of the specimens’ shape and the observations of the extent of the specimen core post-failure were analyzed. There was insufficient evidence from the laboratory experiments to conclude that there is a difference in …

Assessment Of Air Overpressure From Blasting Using Computational Fluid Dynamics, Cecilia Estefania Aramayo

Theses and Dissertations--Mining Engineering

Air overpressure is a shock wave that occurs when explosives detonate and travel through the air. This can cause damage and annoyance in mining blasts, making it a significant concern for the surroundings of the operation. Currently, the cube root scale distance is used to predict air overpressure, but this method has limitations. To accurately determine air overpressure behavior, a new method is needed. Computational fluid dynamics (CFD) is a reliable and advanced technique that can simulate and solve complex physical problems, including the behavior of air overpressure. In this thesis, two techniques, the bursting balloon, and total pressure boundary, …

Development Of Univariate And Multivariate Forecasting Models For Methane Gas Emissions In Underground Coal Mines, Juan Diaz

Theses and Dissertations--Mining Engineering

Methane gas management continues to be a challenge concerning underground coal mine safety and productivity worldwide despite the extraordinary effort of the mining industry, governmental agencies, and academia to develop new technologies to monitor and control methane gas emissions more efficiently. The risk of hazardous methane gas concentrations in underground environments cannot be underestimated. Statistical data for the last 100 years indicate that around 80% of the accidents and 90% of the fatalities in the underground coal mining industry in the US were related to methane gas explosions.

Modern underground mine operations monitor and evaluate atmospheric parameters such as barometric …

Laptop Recycling Case Study: Estimating The Contained Value And Value Recovery Process Feasibility Of End-Of-Life Consumer Electronics, Zebulon Hart

Theses and Dissertations--Mining Engineering

Work has been done to establish, through the development and use of novel assay techniques and analysis metrics, the contained value of a sampling of laptop computers (as an analog for myriad e-waste sources). This work has conceptualized e-waste as an alternative to geologic-origin complex metallic ores and has likewise evaluated the feasibility of value recovery from e-waste sources in a similar manner to an ore. The application of conventional and novel mineral separation techniques to e-waste recycling processes has been evaluated and positive results are demonstrated. Further, this work has demonstrated the ability to identify the presence of base …

Investigation Into, & Analysis Of Temperature & Strain Data For Coal Mine Seal Material During Curing, Stephanus Jaco Van Den Berg

Theses and Dissertations--Mining Engineering

On Monday, January 2, 2006, an underground explosion occurred at the Sago Mine WV, resulting in the death of 12 miners and seriously injury to one miner. On Saturday, May 20, 2006, an underground explosion occurred at the Darby Mine No.1 KY, resulting in five miner’s deaths and one miner’s injury.

The explosion of methane gas and coal dust result in many fatalities in the coal mining industry.

The coal mining industry uses mine seals to optimize the ventilation network. Those structures are designed not only to direct the air appropriately, but also, they should be capable of withstanding some …

Development Of Univariate And Multivariate Forecasting Models For Methane Gas Emissions In Underground Coal Mines, Juan Diaz

Theses and Dissertations--Mining Engineering

Methane gas management continues to be a challenge concerning underground coal mine safety and productivity worldwide despite the extraordinary effort of the mining industry, governmental agencies, and academia to develop new technologies to monitor and control methane gas emissions more efficiently. The risk of hazardous methane gas concentrations in underground environments cannot be underestimated. Statistical data for the last 100 years indicate that around 80% of the accidents and 90% of the fatalities in the underground coal mining industry in the US were related to methane gas explosions.

Modern underground mine operations monitor and evaluate atmospheric parameters such as barometric …

Strain Energy Analysis Related To Strata Failure During Caving Operations, Caroline Gerwig

Theses and Dissertations--Mining Engineering

For stiff beams that can form over the gob of longwall panels, the potential seismic magnitude of the energy released upon strata caving is estimated. Analytical calculations are used to verify two-dimensional models of longwall roof beams to determine the strain energy and gravitational energy developed, that will then be released to surrounding mine workings. Models are developed using RS2 to model the stress, strain, and deflection along the bottom of the longwall roof beam to calculate gravitational and strain energies.

The total energy is then converted to seismic magnitude. Strain energy was consistently less than gravitational energy, except for …

Parametric Numerical Analysis Of Inclined Coal Pillars, Robin Flattery

Theses and Dissertations--Mining Engineering

Pillars are used as the primary support structures for underground mining to maintain stability by supporting the over laying strata. In the case of horizontal seams, the pillars are typically subjected to axial loading due to the weight of the overburden and/or abutment stresses, while in the case of inclined seams they are subjected to oblique loading due to both the vertical and horizontal in-situ stress. Over the years numerous studies have been completed on square and rectangular pillars in horizontal seams that have resulted in several pillar stability equations and criteria. However very few studies are available with respect …

Capture Of Respirable Dust Using Maintenance Free Impingement Screen, Neeraj Kumar Gupta

Theses and Dissertations--Mining Engineering

Dust produced during mining activities has a detrimental effect on both miners’ health and operations’ safety. There is no definitive treatment for coal miners’ pneumoconiosis (CWP), which is caused by prolonged inhalation of respirable dust. Elevated coal dust concentrations have also been shown to cause several disastrous explosions in the United States and worldwide, resulting in the death of miners and loss of operations. Flooded-bed dust scrubbers are used on all modern-day continuous miners. These devices cleanse the dust-laden air and assist in bringing fresh air towards the mining face. Scrubbers use a multi-layered fibrous screen to capture airborne particles. …

Application Of A Novel Ventilation Simplification Algorithm, Caitlin V. Strong

Theses and Dissertations--Mining Engineering

Ventilation network analysis is an integral part of maintaining a safe mine environment. Despite its important role, liberties are often taken with the representation of networks in ventilation network analysis software. In order to provide an alternative to heuristic methods used by ventilation engineers, a simplification algorithm has been developed. This algorithm is designed to work as a compliment to ventilation software. Comparisons of original ventilation networks and simplified networks show little to no change in fan operating point. The program utilizing this algorithm provides an alternative to reducing networks with a parallel factor. It can also be used in …

Development Of An Autonomous Navigation System For The Shuttle Car In Underground Room & Pillar Coal Mines, Vasileios Androulakis

Theses and Dissertations--Mining Engineering

In recent years, autonomous solutions in the multi-disciplinary field of the mining engineering have been an extremely popular applied research topic. The growing demand for mineral supplies combined with the steady decline in the available surface reserves has driven the mining industry to mine deeper underground deposits. These deposits are difficult to access, and the environment may be hazardous to mine personnel (e.g., increased heat, difficult ventilation conditions, etc.). Moreover, current mining methods expose the miners to numerous occupational hazards such as working in the proximity of heavy mining equipment, possible roof falls, as well as noise and dust. As …

Modeling Of Rare Earth Solvent Extraction Process For Flowsheet Design And Optimization, Vaibhav Kumar Srivastava

Theses and Dissertations--Mining Engineering

The separation and purification of rare earth elements (REEs) into individual products has been a topic of significant interest for researchers and engineers for many decades. The prime reason for such sustained interest is due to REEs’ demand and application in modern technology, as well as the challenges associated with their separation and purification. The chemical similarity of rare earth group elements is responsible for difficult separability which makes purification of individual elements challenging. Despite associated complications, processes such as solvent extraction (SX) and ion-exchange have been successfully utilized in the separation and production of REEs on pilot and commercial …

Investigation Of Coal Burst Potential Using Numerical Modeling And Rock Burst Indices, Cristian David Cardenas Triana

Theses and Dissertations--Mining Engineering

Coal bursts are typically defined as a rapid failure of coal or surrounding rock producing a violent release of energy and ejection of rock particles. This phenomenon is extremely complex and dynamic, and this has made it very difficult to predict. In the last decades, different researchers have aimed to understand the sources and mechanisms of failure of coal bursts. Various indices have been developed to assess the burst potential such as the Burst Potential Index (BPI), Energy Storage Rate, and the Strain Energy Density. Lately, numerical modeling has also been used as a tool to examine the rock deformation …

An Approach For Predicting Flow Characteristics At The Continuous Miner Face, Kayla Henderson

Theses and Dissertations--Mining Engineering

As coal and rock are mined, dust is dispersed into the air. This dust, among other contaminants, poses a serious health and safety risk to mineworkers. Very fine dust known as respirable dust can infiltrate the deepest part of the lungs, and long-term exposure to these particles leads to a disease called coal worker’s pneumoconiosis (CWP). Occurrence of this disease declined steadily over the latter half of the 20^th century; however, a recent study indicates that CWP has reemerged with an upward trend beginning at the turn of the century. To combat dust exposure, mine operators use a combination …

Oxidation Pretreatment For Enhanced Leachability Of Rare Earth Elements From Bituminous Coal Sources, Tushar Gupta

Theses and Dissertations--Mining Engineering

Rare earth elements (REEs) are critical components in advanced electronics, clean energy technologies, and national energy and economic security. The global supply situation of these strategically valuable elements remains critical as the market is largely monopolistic. Thus, to alleviate the dependence on global imports, investments are being made in the research and development of innovative and cost-effective technologies for the indigenous processing and recovery of REEs from alternate sources that are cheap and abundant. Numerous research findings have identified potential benefits and proven the technological feasibility of extracting and selectively concentrating REEs from coal byproducts such as preparation plant rejects …

Concepts For Development Of Shuttle Car Autonomous Docking With Continuous Miner Using 3-D Depth Camera, Sibley Miller

Theses and Dissertations--Mining Engineering

In recent years, a great deal of work has been conducted in automating mining equipment with the goals of increasing worker health and safety and increasing mine productivity. Automating vehicles such as load-haul-dumps been successful even in underground environments where the use of global positioning systems are unavailable. This thesis addresses automating the operation of a shuttle car, specifically focusing on positioning the shuttle car under the continuous miner coal-discharge conveyor during cutting and loading operations. This task requires recognition of the target and precise control of the tramming operation because a specific orientation and distance from the coal discharge …

A Methodology For Autonomous Roof Bolt Installation Using Industrial Robotics, Anastasia Xenaki

Theses and Dissertations--Mining Engineering

The mining sector is currently in the stage of adopting more automation, and with it, robotics. Autonomous bolting in underground environments remains a hot topic for the mining industry. Roof bolter operators are exposed to hazardous conditions due to their proximity to the unsupported roof, loose bolts, and heavy spinning mass. Prolonged exposure to the risk inevitably leads to accidents and injuries.

The current thesis presents the development of a robotic assembly capable of carrying out the entire sequence of roof bolting operations in full and partial autonomous sensor-driven rock bolting operations to achieve a high-impact health and safety intervention …

Proof Of Concept For The Development Of A Ground Vibration Sensor System For Future Research In Blasting, John Meuth

Theses and Dissertations--Mining Engineering

Ground vibrations from blasting are one of the leading limitations to mining (underground and surface). There is a need for a low-cost scalable vibration monitoring system to conduct large scale ground vibration projects in the mining industry. Studies conducted on ground vibrations use any number of different sensors to obtain their data, the different sensor capabilities and methods for data processing lead to uncertainties in the research and regulations set for ground vibrations. Commercial Systems do not allow researchers to obtain raw output data, and the data processing procedures are not provided or disclosed for these systems. In order to …

The Effect Of Delay And Sequence On Blasting Fragmentation Results, Tristan Worsey

Theses and Dissertations--Mining Engineering

Blasters use the delay between charges and the firing sequence of the explosive charges to help reduce vibrations and achieve the desired fragmentation. Although delay and sequence are recognized as very important for vibrations and fragmentation, only vibration models consider timing as a variable in the prediction tool, without any known model for fragmentation prediction based on the delay sequence. Of the few fragmentation models available, very few take delay into account and do not give guidance on row delay and/or sequence selections. With the invention of electronic detonators in 1984, there are new avenues to explore with sequence and …

Numerical Approximation Of The Ground Reaction And Support Reaction Curves For Underground Limestone Mines, Jesus Castillo Gomez

Theses and Dissertations--Mining Engineering

Pillar stability has been a matter of study for the last 70 years. The determination of pillar strength had taken different solutions and approaches over that time. This research has led to numerous empirical formulations that have reduced the number of pillar failures worldwide. However, new numerical approaches are being studied. In the last 20 years, the Ground Reaction Curve concept has been examined as a way of understanding the convergence of the rock-mass. Although the Ground Reaction Curve was first introduced in the civil tunneling industry, several authors have introduced the Ground Reaction Curve concept as an approach for …

Predicting Fracture Extension Around A Borehole Using The Numerical Displacement Discontinuity Method, Nathaniel Schaefer

Theses and Dissertations--Mining Engineering

Prediction of blast damage radius is integral in the optimization of mining safety and production. The damage radius can be related to blasting variables such as fragmentation size as well as overbreak in hard rock. Various methods have been developed to predict and assess damage radius extension for individual holes to aid in blast design. These methods range from experimental and observational techniques to theoretical applications. Some of these methods have been used with a degree of success. However, many of them lack a comprehensive combination of experimental and theoretical contributions. Since post-blast environments are not conducive to assessing whether …

Characterization Of Rare Earth Elements In The Illinois Basin Coals, Alireza Valian

Theses and Dissertations--Mining Engineering

The purpose of this study is to characterize the distribution and occurrence of rare earth elements (REEs) in the coal and coal-related material from the Illinois Basin. For characterizing the distribution of REEs, 17 core samples were investigated from various parts in the basin. Also, several individual samples from coal preparation plants and isolated geological occurrences were included in the study. In result, the average REE concentrations were calculated on a bed-to-bed basis, although the distribution of REEs in the coal beds was found laterally and vertically heterogeneous. A number of trends were found that describe the variations. Most importantly, …

Investigation Into Mine Pillar Design And Global Stability Using The Ground Reaction Curve Concept, Ravi Chandan Ray

Theses and Dissertations--Mining Engineering

Pillars form an important support structure in any underground mine. A bulk of the overburden load is borne by the mine pillars. Thus, the strength of pillars has been a subject of detailed research over more than 6 decades. This work has led to the development of largely empirical pillar design formulations that have reduced the risk of pillar failures and mine collapse. Current research, however, has drawn attention to the fact that some of the assumptions used in the development of conventional pillar design methodologies are not always valid. Conventional pillar design methodology assumes that the pillars carry the …

Predictive Modeling Of Dc Arc Flash In 125 Volt System, Austin Cody Gaunce

Theses and Dissertations--Mining Engineering

Arc flash is one of the two primary hazards encountered by workers near electrical equipment. Most applications where arc flash may be encountered are alternating current (AC) electrical systems. However, direct current (DC) electrical systems are becoming increasingly prevalent with industries implementing more renewable energy sources and energy storage devices. Little research has been performed with respect to arc flash hazards posed by DC electrical systems, particularly energy storage devices. Furthermore, current standards for performing arc flash calculations do not provide sufficient guidance when working in DC applications. IEEE 1584-2002 does not provide recommendations for DC electrical systems. NFPA 70E …