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- Aquiclude (1)
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Articles 1 - 12 of 12
Full-Text Articles in Mining Engineering
Separation Of Radionuclides From A Rare Earth-Containing Solution By Zeolite Adsorption, Deniz Talan, Qingqing Huang
Separation Of Radionuclides From A Rare Earth-Containing Solution By Zeolite Adsorption, Deniz Talan, Qingqing Huang
Faculty & Staff Scholarship
The increasing industrial demand for rare earths requires new or alternative sources to be found. Within this context, there have been studies validating the technical feasibility of coal and coal byproducts as alternative sources for rare earth elements. Nonetheless, radioactive materials, such as thorium and uranium, are frequently seen in the rare earths’ mineralization, and causes environmental and health concerns. Consequently, there exists an urgent need to remove these radionuclides in order to produce high purity rare earths to diversify the supply chain, as well as maintain an environmentally-favorable extraction process for the surroundings. In this study, an experimental design …
Coupling Simulation Model Between Mine Ventilation Network And Gob Flow Field, F.I. Wu, Y. Luo, X-T Chang
Coupling Simulation Model Between Mine Ventilation Network And Gob Flow Field, F.I. Wu, Y. Luo, X-T Chang
Faculty & Staff Scholarship
Many numerical simulation studies of coal spontaneous combustion have focused on the leakage flow field in the mine gob. However, most of these studies isolate the gob from the mine ventilation system, failing to consider the effects of air leakage on gob boundary conditions. A novel model coupling the mine ventilation network (MVN) and gob flow field (GFF) has been developed to simulate the overall mine ventilation system. The concept of network boundary node was proposed and the corresponding air flow rate balance equations were developed based on the node pressure method for MVN calculation and the finite element method …
Vertical Stress And Deformation Characteristics Of Roadside Backfilling Body In Gob-Side Entry For Thick Coal Seams With Different Pre-Split Angles, Yuqi Ren, Guorui Feng, Pengfei Wang, Jun Guo, Yi Luo, Ruipeng Qian, Qiang Sun, Songyu Li, Yonggan Yan
Vertical Stress And Deformation Characteristics Of Roadside Backfilling Body In Gob-Side Entry For Thick Coal Seams With Different Pre-Split Angles, Yuqi Ren, Guorui Feng, Pengfei Wang, Jun Guo, Yi Luo, Ruipeng Qian, Qiang Sun, Songyu Li, Yonggan Yan
Faculty & Staff Scholarship
Retained gob-side entry (RGE) is a significant improvement for fully-mechanized longwall mining. The environment of surrounding rock directly affects its stability. Roadside backfilling body (RBB), a man-made structure in RGE plays the most important role in successful application of the technology. In the field, however, the vertical deformation of RBB is large during the panel extraction, which leads to malfunction of the RGE. In order to solve the problem, roof pre-split is employed. According to geological conditions as well as the physical modeling of roof behavior and deformation of surrounding rock, the support resistance of RBB is calculated. The environment …
Evaluation Of Frother Types For Improved Flotation Recovery And Selectivity, Qingqing Huang, Xinbo Yang, Rick Q. Honaker
Evaluation Of Frother Types For Improved Flotation Recovery And Selectivity, Qingqing Huang, Xinbo Yang, Rick Q. Honaker
Faculty & Staff Scholarship
A laboratory study was conducted to evaluate and compare the effectiveness of nine different frother types when used in a three-phase, continuously operating froth flotation system. The frothers included several that are commonly used in the industry (e.g., MIBC, 2EH, and F-1) as well as unique frother types (e.g., F-3). The tests were conducted in a 5-cm diameter laboratory flotation column that provided near plug-flow mixing conditions due to a length-to-diameter ratio of around 50:1. Test results indicate that F-1, MIBC, and MPC (in order of decreasing effectiveness) provided the weakest performance in terms of combustible recovery while F-2, MAC, …
Using Lamodel To Analyze Coal Bumps, Keith A. Heasley, Ihsan Berk Tulu
Using Lamodel To Analyze Coal Bumps, Keith A. Heasley, Ihsan Berk Tulu
Faculty & Staff Scholarship
Coal bumps have long been a safety hazard in coal mines, and even after decades of research, the exact mechanics that cause coal bumps are still not well understood. Therefore, coal bumps are still difficult to predict and control. The LaModel program has a long history of being used to effectively analyze displace- ments and stresses in coal mines, and with the recent addition of energy release and local mine stiffness calculations, the LaModel program now has greatly increased capabilities for evaluating coal bump potential. This paper presents three recent case histories where coal stress, pillar safety factor, energy release …
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
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 …
Numerical Analysis And Case Study On The Mitigation Of Mining Damage To The Floor Of No. 5 Coal Seam Of Taiyuan Group By Grouting, A. Li, Y. Liu, L. Mou, K. Li
Numerical Analysis And Case Study On The Mitigation Of Mining Damage To The Floor Of No. 5 Coal Seam Of Taiyuan Group By Grouting, A. Li, Y. Liu, L. Mou, K. Li
Faculty & Staff Scholarship
Based on the geological condition of panel 22507 of the no. 5 coal seam at Dongjiahe coal mine, numerical analysis of the stability and water permeability of the floor aquiclude before and after grouting was conducted using Rock Failure Process Analysis (F-RFPA2D). The dynamic development, extension, and distribution of the cracks in the aquiclude are discussed. It is shown that grouting can increase the effective thickness of the aquiclude, reduce the floor damage depth, and control the floor water inrush path, thus effectively improving the overall strength and water blocking capability of the aquiclude. These numerical study results were applied …
Dynamic Mechanical Behavior Of Dry And Water Saturated Igneous Rock With Acoustic Emission Monitoring, Jun Guo, Guo-Rui Feng, Ting-Ye Qi, Pengfei Wang, Jian Yang, Zhen Li, Jinwen Bai, Xianjie Du, Zehua Wang
Dynamic Mechanical Behavior Of Dry And Water Saturated Igneous Rock With Acoustic Emission Monitoring, Jun Guo, Guo-Rui Feng, Ting-Ye Qi, Pengfei Wang, Jian Yang, Zhen Li, Jinwen Bai, Xianjie Du, Zehua Wang
Faculty & Staff Scholarship
The uniaxial cyclic loading tests have been conducted to study the mechanical behavior of dry and water saturated igneous rock with acoustic emission (AE) monitoring. The igneous rock samples are dried, naturally immersed, and boiled to get specimens with different water contents for the testing. The mineral compositions and the microstructures of the dry and water saturated igneous rock are also presented. The dry specimens present higher strength, fewer strains, and rapid increase of AE count subjected to the cyclic loading, which reflects the hard and brittle behavior and strong burst proneness of igneous rock. The water saturated specimens have …
Analysis Of Monitored Ground Support And Rock Mass Response In A Longwall Tailgate Entry, G.S. Esterhuizen, D.F. Gearhart, I.B. Tulu
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 …
Geotechnical Considerations For Concurrent Pillar Recovery In Close-Distance Multiple Seams, Peter Zhang, Berk Tulu, Morgan Sears, Jack Trackemas
Geotechnical Considerations For Concurrent Pillar Recovery In Close-Distance Multiple Seams, Peter Zhang, Berk Tulu, Morgan Sears, Jack Trackemas
Faculty & Staff Scholarship
No abstract provided.
Deep Cover Bleeder Entry Performance And Support Loading: A Case Study, Ted M. Klemetti, Mark Alexander Van Dyke, Ihsan Berk Tulu
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 …
Analysis Of Global And Local Stress Changes In A Longwall Gateroad, I.B. Tulu, G.S. Esterhuizen, D. Gearhart, T.M. Klemetti, K.M. Mohamed, D.W.H. Su
Analysis Of Global And Local Stress Changes In A Longwall Gateroad, I.B. Tulu, G.S. Esterhuizen, D. Gearhart, T.M. Klemetti, K.M. Mohamed, D.W.H. Su
Faculty & Staff Scholarship
A numerical-model-based approach was recently developed for estimating the changes in both the hor- izontal and vertical loading conditions induced by an approaching longwall face. In this approach, a sys- tematic procedure is used to estimate the model’s inputs. Shearing along the bedding planes is modeled with ubiquitous joint elements and interface elements. Coal is modeled with a newly developed coal mass model. The response of the gob is calibrated with back analysis of subsidence data and the results of previously published laboratory tests on rock fragments. The model results were verified with the sub- sidence and stress data recently …