Mining Engineering Commons^™

Selective Recovery Of Critical Minerals (Ni, Zn, Co, And Mn) From Acid Mine Drainage Utilizing Ion Exchange And Selective Precipitation Processes, Esteban Albeiro Cardenas Restrepo

Graduate Theses, Dissertations, and Problem Reports (ETD)

Critical minerals (CMs) are essential for U.S. national security and technological development. The U.S. heavily depends on imports of these minerals from other countries, making supply chain disruptions a likely scenario. In consequence, finding alternative sources to conventional mining for these elements has become a topic of interest in recent years. Acid Mine Drainage (AMD), once solely viewed as an environmental problem, has emerged as a potential alternative source for CMs. AMD is a naturally occurring process where surface and underground water interact with sulfur-bearing minerals in the presence of oxygen and microorganisms. This interaction causes the water to become …

Delineating Underground Geological Formations: An Integrated Lidar And Camera-Based Approach For Enhanced Feature Identification In Poorly Lit Mining Environments, Timothy James Batchler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Underground mining environments present challenges in accurately identifying geological formations and potential hazards due to poor lighting conditions and confined spaces. Traditional imaging methods often fall short, making it difficult to detect critical geological features such as limestone, shale, and other rock formations. This research addresses these challenges by integrating camera imagery with Light Detection and Ranging (LiDAR) data to improve geological formation detection in poorly lit mining settings.

LiDAR, with its ability to generate high-resolution three-dimensional models in low-light or dark conditions, offers a promising solution to these limitations. By combining LiDAR’s precise 3D models with camera imagery, the …

Enhancing Pillar Stability Assessment In Underground Limestone Mines Using Lamodel: Integrating Empirical Strength Equations For Improved Ground Control, Alim Elibol

Graduate Theses, Dissertations, and Problem Reports (ETD)

Underground stone mining accounts for approximately 21% of all underground mining operations in the United States, with more than 2,000 workers employed in this sector as of 2019. Ground control failures, particularly those involving massive pillar collapses and roof falls, pose significant safety hazards, contributing to 40% of fatalities and 15% of lost workdays since 2006. Several massive pillar collapses have occurred in active limestone mines from 2015 to 2021, and a fatal incident was reported in January 2022 in a mine operating within the Loyalhanna formation. Given these risks, accurate stability assessment tools are essential for improving mine safety. …

Investigation Of Spalling Effects On The Brittle Behavior Of Rectangular Pillars In Underground Stone Mines, Yolver Yesid Jimenez Ibanez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recent catastrophic collapses in U.S. limestone mines have exposed the limitations of traditional empirical design formulas for brittle rock masses. These events, especially those involving slender pillars, underscore that traditional methods often fail to account for progressive, spalling-dominated failure, highlighting a crucial gap in our understanding. This research addresses this issue by conducting a comprehensive investigation into the mechanics of spalling in rectangular stone mine pillars, utilizing advanced three-dimensional numerical modeling with FLAC3D combined with LiDAR-based geometric modeling.

The stability of a pillar is governed by a complex interaction between the in-situ stress field, rock mass properties, and pillar geometry. …

Rare Earth Element Recovery From Acid Mine Drainage Using Ion Exchange And Selective Precipitation Processes, Paubla Andrea Gallego Lopez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rare earth elements (REEs) are used in high-tech applications due to their electromagnetic and optical properties. As global demand for REEs surges, the limitation of primary mineral deposits has increased interest in alternative sources. One such source is acid mine drainage (AMD), which, although typically low in REE concentration, offers a promising avenue for recovery. Among the emerging recovery methods, ion exchange has shown promise due to its effectiveness at low concentrations and lower operational cost than conventional techniques such as acid leaching and solvent extraction.

This research focused on developing a recovery process by combining ion exchange with selective …

Investigating Critical Mineral Recovery And Carbon Mineralization Potential In Coal Fly Ash, Syabilla Cardosh

Graduate Theses, Dissertations, and Problem Reports (ETD)

Coal fly ash (CFA), a byproduct of coal combustion, represents an innovative opportunity to address the rising demand for critical minerals and the need to reduce CO2 emissions due to its significant concentrations of calcium and magnesium. By providing insights and preliminary data, this study aims to contribute to the foundational understanding necessary for future development.

A multidisciplinary approach was employed to assess CFA’s potential, including detailed chemical and mineralogical characterization using X-ray fluorescence (XRF), inductively coupled plasma mass spectrometry (ICP-MS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). XRD analysis revealed crystalline phases in the CFA samples. At the …

Performance And Field Testing Of Geotextiles For Dewatering Rare Earth Element Hydraulic Preconcentrate From Hardrock Amd, Ian R. Bird

Graduate Theses, Dissertations, and Problem Reports (ETD)

As part of ongoing efforts to develop a domestic Rare Earth Elements (REE) supply chain the Hydraulic Preconcentrate (HPC) produced at the Horseshoe bend treatment plant (HsB) was manufactured and evaluated as a potential source for feedstock. After the existing clarifiers on the site were flipped to the desired pH set points, HPC was manufactured and pumped to 24 geobags. The geobags were then passively dewatered to increase the total solids percentage. The geobags evaluated were comprised of: Woven geotextiles, composite (woven and non- woven), and geobags augmented with Capillary Channel Fiber (CCF). Column Filtration Tests (CFTs) were performed onsite …

Characterization And Evaluation Of Various Biochar Types As Green Adsorbents For Rare Earth Element Recovery From Aqueous Solutions, Oluwaseun Victor Famobuwa

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rare earth elements (REEs) are members of the lanthanide family (atomic number 57 – 71). They are significantly important to the global economy due to their applications in renewable energy, defense, and medical industries. REEs are primarily derived from bastnaesite and monazite but may also be present in xenotime, cerite, alanite, and many other types of mineralization in lesser amounts. Due to the increasing demand for REEs and their criticality in the supply chain, the need to explore secondary sources of REEs has gained tremendous importance.

Secondary sources of REEs include but are not limited to acid mine drainage (AMD), …

Analysis Of The Root Causes Of Fatal Injuries In The United States Surface Mines Between 2008 And 2021., Maria Fernanda Quintero

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mining has long been recognized as a hazardous industry worldwide. An annual average rate of 10.3 fatal injuries per 100,000 workers was recorded in the United States between 2008 and 2021 (MSHA, 2022). This rate can be compared with the average of the industries with the highest average rates of fatal injuries—agriculture, forestry, fishing, and hunting; transportation and warehousing; and construction—which had average rates of 23.5, 13.1, and 9.9 fatal injuries per 100,000 workers, respectively, during the same period in the Unites States (U.S. Bureau of Labor Statistics, 2023).

The scope of this research is related to the fatal injuries …

Augmented Reality And Mobile Systems For Heavy Equipment Operators In Surface Mining, Juan David Valencia Quiceno

Graduate Theses, Dissertations, and Problem Reports (ETD)

U.S. federal laws mandate that mining companies ensure a safe workplace, implement approved training programs, and promptly report work-related injuries. The mining industry's commitment to innovation reflects a history of adopting advancements to enhance environmental sustainability, workplace safety, and overall productivity, while simultaneously reducing operational costs. This thesis proposes the integration of Augmented Reality (AR) technology and digital applications to enhance the surface mining industry, presenting two innovative solutions: an AR Training System and an Operational Digital System. These business solutions have been developed and applied at a surface mine in the southwest of the US, having the potential to …

Development Of A Hydrometallurgical Process For The Extraction Of Cobalt, Manganese, And Nickel From Acid Mine Drainage Treatment Byproduct, Alejandro Agudelo Mira

Graduate Theses, Dissertations, and Problem Reports (ETD)

Critical minerals (CMs) are defined as crucial elements for the country's economy due to the development of new cutting-edge applications and the risk of an eventual disruption in their supply chain. The unique chemical and physical properties of the CMs have made these elements decisive in the growth of industries such as telecommunications, army, medicine, Aerospace, etc. In 2022, the US Geological Survey established a list of 50 CMs, including manganese, cobalt, nickel, aluminum, magnesium, and others. Of the total of CMs, 26 are 100% imported from outside the United States (Venditti, 2022).

Driven by the ever-increasing demand for critical …

Analysis Of The Brittle Failure Mechanism Of Underground Stone Mine Pillars By Implementing Numerical Modeling In Flac3d, Rosbel Jimenez

Graduate Theses, Dissertations, and Problem Reports (ETD)

The room and pillar mining method is the most commonly utilized method for extracting minerals found in flat-lying stratiform, and it has been used in the majority of underground stone mines in the United States (Esterhuizen et al., 2011), as a consequence, it is a primary topic of study in the mining field. If a set or layout of pillars is unstable, it can cause a major collapse, resulting in not only the destruction of the underground mine, but also air blast, subsidence, and convergence of the mine opening, especially if they occur in a short period of time (Esterhuizen …

Selective Recovery Of Rare Earth Elements From Acid Mine Drainage Treatment Byproduct, Zeynep Cicek

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rare earth elements (REEs) are critical in emerging clean energy, advanced technologies, and military defense applications due to their unique physical, chemical, optical, and luminescent properties. Given the potential supply chain restrictions imposed by one country's dominance in the global REE market and the consistently growing demand for REEs, developing the US domestic REE supply chain is imperative. Thus, alternative sources are crucial to supply the demand and prevent interruption in manufacturing products that consume REEs. Concurrently, acid mine drainage (AMD) is a long-standing and widespread global challenge the mining industry encounters. AMD is generated in large volumes and continuously …

Identification Of Rockmass Deformation And Lithological Changes In Underground Mines By Using Slam-Based Lidar Technology, Francisco Eduardo Gil Hurtado

Graduate Theses, Dissertations, and Problem Reports (ETD)

In mining, hazards causing rib and roof fall accidents generally develop with time. The development of a hazard depends on factors like geology, excavation geometry, overburden stress, and mining-induced stresses. Hazard mapping in an underground mine is essential for roof and rib stability assessment. However, often it is neither practical nor economical to inspect and map vast areas of mine workings with limited personnel. New technologies, recently, have been adopted in the mining industry that can solve this problem. Advances in LiDAR technology and simultaneous localization and mapping (SLAM) algorithms have led to the development of portable and mobile laser …

Development Of An Entry-Scale Modeling Methodology To Provide Ground Reaction Curves For Longwall Gateroad Support Evaluation, Haochen Zhao

Graduate Theses, Dissertations, and Problem Reports (ETD)

Longwall gateroad entries are generally subjected to severe mining-induced stress changes and deformations; they are prone to large roof falls, floor heaves, and rib sloughing. The standing support system in underground mines needs to be carefully designed to compensate for the mining-induced deformation of the surrounding rock mass and consecutively protect the integrity of gateroad entries. Local geology, together with mining-induced stress redistribution, influences the ground response and plays a major role in the performance of a standing support design. In the US, Support Technology Optimization Program (STOP) and its Ground Reaction Curve (GRC) design criteria have been applied to …

Integrated Large Discontinuity Factor, Lamodel And Stability Mapping Approach For Stone Mine Pillar Stability, Mustafa Baris Ates

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this research is to develop a software tool that integrates the large discontinuity factor (LDF) and the Boundary Element Method software (BEM), LaModel, to allow stone mine operators to assess the impact of the large discontinuities on local pillar stability. National Institute for Occupational Safety and Health (NIOSH) published design guidelines for underground stone mines to guide the industry in designing pillar and roof support. These guidelines emphasize the impact of large, angular discontinuities on pillar strength. Esterhuizen et al. (2011) derived the large discontinuity factor (LDF) to account for the impact of discontinuities on pillar stability …

Investigation Of Geomechanical Behavior Of Laminated Rock Mass Through Experimental And Numerical Approach, Qingwen Shi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Roof failure in the Appalachian underground coal fields occurs often in laminated shale. Laminated shale roof in coal mines fails in unique ways, such as cutter failure or delamination failure. Extensive studies have investigated the influential factors that cause laminated roof failure, which include in-situ stress, entry layout, roof span, and roof support. However, cutter failure continues to occur frequently and erratically. This is due to the lack of in-depth understanding of the inherent properties of the laminations, such as bedding plane strength, matrix strength, and bedding plane spacing, which in turn influence the geomechanical behavior of the laminated rock. …

Noise Exposure Trends Among Violating Coal Mines, 2000 To 2021, Hanna Grace Davis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Noise-induced hearing loss has continued to be a significant issue within the mining industry, even after the passing of the MSHA’s improved noise standard in 2000. NIOSH has recognized that the noise standard enacted by both MSHA and OSHA does not properly protect workers with the 5 dBA exchange rate (i.e., the increase in noise level leading to a doubling of energy) and the lack of emphasizing the use of engineering controls over administrative controls and overreliance on hearing protection device usage. The primary objective of this study is to investigate statistical sound relationships between MSHA noise-related violations and samples …

Calcite Depression In Bastnaesite-Calcite Flotation System Using Organic Acids, Emmy Muhoza

Graduate Theses, Dissertations, and Problem Reports (ETD)

Bastnaesite is the primary source of light REEs, namely cerium (Ce), lanthanum (La), praseodymium (Pr), neodymium (Nd), to name a few. Bastnaesite is typically concentrated using the froth flotation beneficiation method. Flotation of bastnaesite suffers from high reagent consumption due to the similar surface characteristics of bastnaesite and associated gangue minerals, including calcite. Additionally, complex stages of high-temperature conditioning are often required to suppress the detrimental impact of dissolved calcium ions on the flotation of bastnaesite. This research seeks to investigate the capabilities of organic acids in the bastnaesite-calcite flotation systems to selectively depress calcite minerals and effectively chelate calcium …

Experimental And Theoretical Investigation On The Initiation Mechanism Of Low-Rank Coal's Self-Heating Process, Yinan Zhang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Coal spontaneous combustion remains a safety concern during coal mining, transportation, and storage and requires further investigation to develop effective prevention and control strategies. While various intrinsic and extrinsic conditions may influence coal self-heating, low-rank coals are more prone to spontaneous combustion, especially in humid climates. Therefore, quantifying the effect of extrinsic moisture on the self-heating of low-rank coals is critical for understanding the high propensity of low-rank coals for spontaneous combustion. Many studies have qualitatively evaluated the role of extrinsic moisture on the coal self-heating. Despite this, few studies have quantified the contribution of extrinsic moisture on wetting and …

Static Liquefaction In Tailing Dams, Jose Raul Zela Concha

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Fundao tailing dam in Brazil failed on November 5, 2015 causing loss in life, property and severe damage to the environment. The waste flow traveled at 11m/s and approximately 32 million m³ tailings was released into the downstream area. Investigations by regulators concluded that a series of poor designs and construction of the tailing were the causes of the failure. Further investigations also showed that surface failure occurred in the mid height of the slope with a safety factor of 0.52. Both investigations concluded that static liquefaction induced the failure of tailings dam. However, geology variation in the …

Size Effect And Anisotropy On The Strength Of Shale Under Compressive Stress Conditions, Yun Zhao

Graduate Theses, Dissertations, and Problem Reports (ETD)

The underground coal mines in the Appalachian region report the highest rate of roof falls in the United States. The immediate roof of these mines is mostly composed of shale. The in-situ strength of shale is necessary for designing roof support to prevent roof falls. Estimating the in-situ strength of shale requires the knowledge of both size effect and anisotropy. This research used literature review, theoretical analysis, numerical modeling, and laboratory experiment to systematically investigate the size effect and anisotropy of shale strength under compressive strength conditions.

Literature review involved a comprehensive summary of previous research on the size effect …

Implementing The Empirical Stone Mine Pillar Strength Equation Into The Boundary Element Method Software Lamodel, Samuel Escobar

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this research, the equation for the increasing stress into the interior of a stone mine pillar, as a function of the pillar width-to-height ratio, is derived from the empirical pillar strength equation proposed by Esterhuizen et al. (2011). The gradient stress equations for the stone mine pillars were derived by following similar approaches to those presented by Mark et al. (1992) and Johnson et al. (2014). In these approaches, it is assumed that the variation of stresses within the pillar is a function of distance to the closest rib. The stress gradient function provides the stress distribution within the …

Evaluation Of Various Separation Techniques For The Removal Of Actinides From A Rare Earth-Containing Solution Generated From Coarse Coal Refuse, Deniz Talan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rare earth elements have emerged as a vital commodity due to their significance in the production of high-tech devices as well as their utilization in defense and military systems. They are deemed critical due to potential scarcity, supply constraints, and the lack of minable concentrations. Therefore, alternative sources are needed to meet the demand and continue manufacturing rare earth-required products. Coal and coal by-products, in that regard, have presented a significant opportunity and proven to contain a considerable amount of rare earths. However, toxic elements such as thorium and uranium are frequently seen in the same mineralization as rare earths. …

Recovery Of Phosphorus From Florida Phosphatic Waste Clay, Amir Eskanlou

Graduate Theses, Dissertations, and Problem Reports (ETD)

This MS thesis examines the recovery of phosphorus (P) from Florida waste clay (WC). A comprehensive literature review revealed that: (i)-The most important values being lost to WC are P and rare earth elements (REEs). For the recovery of these values from WC, two crucial attempts are the removal of extremely fine-sized clays, followed by the recovery of phosphate content, which can pave the path for the recovery of REEs; (ii)-Any scientific/ technological solution should, at the same time, be economically and environmentally attractive to the industry. As such, moving from mostly chemical separation processes to the primarily physical/ physicochemical …

Optimization Of Operating Conditions And Design Parameters On Coal Ultra-Fine Grinding Through Kinetic Stirred Mill Tests And Numerical Modeling, Francisco Patino

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study investigated the ultra-fine coal grinding performance of four low- to moderate-cost grinding media: ceramic balls, granular sand, alumina beads, and silica beads. The kinetic grinding tests were conducted using a stirred mill, while different operating conditions, including the media size, solids concentration, and the addition of viscosity modifiers, were examined. Characterization studies in terms of particle size, shape, and surface morphology were further performed to support the experimental findings. Moreover, using population balance modeling, grinding simulation was performed in Matlab to forecast the particle size distribution based on the specific energy input and experimental size-related data. The results …

Geology Oriented Loading Approach For Underground Coal Mines, Deniz Tuncay

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mining-induced stresses in underground coal mines play a significant role in pillar and support design, hence in the safety of mining operations. Adequate design of pillars and roof control plans rely on the accurate assessment of the mining-induced loads, as well as the load-bearing capacities of the supports. In pillar design tools frequently used by the underground coal mining industry and Mine Safety and Health Administration (MSHA), overburden loading is estimated by geometric concepts such as the tributary area and the abutment angle method. These methods do not explicitly consider important mechanical responses such as specific overall ground behavior. The …

Improving Real-Time Methane Monitoring In Longwall Coal Mines Through System Response Characterization Of A Multi-Nodal Methane Detection Network, Brian Philip Cappellini

Graduate Theses, Dissertations, and Problem Reports (ETD)

Machine automation and atmospheric monitoring are used by many industries to improve safety and productivity in the workplace. The underground Methane Watchdog System (MWS) is a multi-nodal network of sensors currently under development. The MWS aims to improve safety and productivity by introducing 10 compact sampling units designed to be easily integrated within the current roof support equipment of the mine. Each unit contains an array of sensors used to continuously monitor the environmental conditions which include methane concentration, temperature, pressure, and relative humidity. All MWS units report information back to a remote central processing hub (CPH) which collects nodal …

Evaluation Of Lidar Systems For Rock Mass Discontinuity Identification In Underground Stone Mines From 3d Point Cloud Data, Mario Alejandro Bendezu De La Cruz

Graduate Theses, Dissertations, and Problem Reports (ETD)

The goal of this thesis is to compare the accuracy and precision of the discontinuity identification results obtained by three active remote sensing technologies along with a point cloud processing program, and the results obtained by conventional methods. For this research, the active remote sensing devices were terrestrial LIDAR, mobile LiDAR with Simultaneous localization, and mapping (SLAM), and LIDAR/Camera on an autonomous UAV. The open-source point cloud data processing programs Discontinuity Set Extractor (DSE) and the Cloud Compare were used to process point cloud data.

The results of this research found that it is possible to identify certain geological structures …

Various Operational Aspects Of The Extraction Of Critical Minerals From Acid Mine Drainage And Its Treatment By-Product, Zhongqing Xiao

Graduate Theses, Dissertations, and Problem Reports (ETD)

Acid mine drainage (AMD) is environmentally hazardous acidic water, which is continuously generated in large volumes at coal mining sites, typically when pyrite is exposed to oxygen and water. As its continuous migration under the geologic conditions, AMD tends to leach metal elements out from the surrounding minerals, leading to high concentrations of metal elements, like iron, aluminum, magnesium, manganese, lead, arsenic, as well as critical cobalt and rare earth elements (REEs). AMD must be treated and monitored to meet the effluent limits, under U.S.C §1251, the Clean Water act, before being discharged to receiving streams.

Recently, the research is …