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Articles 211 - 240 of 3214
Full-Text Articles in Sustainability
Solar Solution For Closed Ccr Units And Adjacent Land, Chris Fairey
Solar Solution For Closed Ccr Units And Adjacent Land, Chris Fairey
World of Coal Ash Proceedings
Solar Solution for Closed CCR Units and Adjacent Land Chris Fairey1, Kenny Hughes1 1Watershed Geo, 1125 Sanctuary Pkwy, Suite 180, Alpharetta, GA 30009 KEYWORDS: Solar, Racking, Brownfield, Greenfield, Slopes, PowerCap® ABSTRACT With the reduction in coal fired power generation, there is a consistent trend in the industry to supplement generation with solar power. The property located within and surrounding these decommissioned power plants offers a significant opportunity to create a renewable solar power asset. The PowerCap® Nail to Rail System, developed by Watershed Geo, is an advanced solar racking solution designed for sites that do not require environmental closure such …
Abundances Of Elements In Global Coals, Shifeng Dai
Abundances Of Elements In Global Coals, Shifeng Dai
World of Coal Ash Proceedings
The abundance of elements in coal is important not only because it provides a solid scientific and practical foundation for various geochemical comparisons, but also because it helps address broader questions in Earth Sciences. In this study, data on major and trace elements in global coals comprising hundreds of thousands of coal samples were compiled from peer-reviewed journal articles, books, various databases, dissertations, and technical reports. These data formed the basis for estimating element abundances in global coals presented in this study. All collected data were rigorously screened for reliability, and any records with questionable quality were excluded from the …
Consolidation Modeling To Support Closure Planning Of An Upstream Raise Ccr Surface Impoundment Containing Fgd Material, Tanya Walkenbach, Craig Schuettpelz, Todd Stong, Shane Stockdill
Consolidation Modeling To Support Closure Planning Of An Upstream Raise Ccr Surface Impoundment Containing Fgd Material, Tanya Walkenbach, Craig Schuettpelz, Todd Stong, Shane Stockdill
World of Coal Ash Proceedings
Rainbow Energy Center’s (REC’s) Coal Creek Station has managed calcium sulfite flue gas desulfurization (FGD) material in composite-lined upstream raise surface impoundments since 2001. The upstream raise surface impoundment utilizes bottom ash (drainage zone) and fly ash (structural zone) produced at Coal Creek Station to contain the FGD placement. FGD material was hydraulically sluiced to the center of the 110-acre Upstream Raise 92 (UR92) coal combustion residual (CCR) unit between 2001 and 2021. The FGD was deposited to a maximum thickness of approximately 100 feet in the center of the unit. Significant consolidation of FGD material occurred with subsequent FGD …
Investigation Of A Historical Coal Combustion Residuals Management Unit (Ccrmu), Todd Stong, Shane Stockdill, Erin Hunter
Investigation Of A Historical Coal Combustion Residuals Management Unit (Ccrmu), Todd Stong, Shane Stockdill, Erin Hunter
World of Coal Ash Proceedings
Rainbow Energy Center’s (REC’s) Coal Creek Station has managed coal combustion residuals (CCR) in various engineered impoundments and landfills since plant operation began in 1978. Since then, waste containment methods have evolved resulting in significant changes to their CCR management practice. In the late 1980s and early 1990s REC closed several existing CCR units with natural soil liners and constructed several new CCR units with composite liner systems. One of the closed units was an area now referred to as North Section 16, an impoundment that received CCR including bottom ash, fly ash, and flue gas desulfurization material. North Section …
Transportation Logistics Panel, John Ward, Andrew Vollmer, Tracy Zea, Marci Jenks
Transportation Logistics Panel, John Ward, Andrew Vollmer, Tracy Zea, Marci Jenks
World of Coal Ash Proceedings
As the industry shifts from freshly generated ash to harvested materials and advanced utilization, logistics is becoming one of the primary drivers of project success or failure. This moderated panel will explore how sourcing, transportation, and storage realities are changing — and what project teams most often underestimate when working with harvested coal ash. Panelists will discuss what breaks, what becomes more complex, and how logistics considerations are reshaping planning and development.
Optimization Of Remedial Strategies For Ccr Site Corrective Action Through Advanced Geochemical Modeling, Cole Mayer, Pj Nolan
Optimization Of Remedial Strategies For Ccr Site Corrective Action Through Advanced Geochemical Modeling, Cole Mayer, Pj Nolan
World of Coal Ash Proceedings
The power industry is actively designing and implementing corrective measures for Coal Combustion Residuals (CCR). In many cases, these measures include active remedies such as pump and treat, in-situ injection, or reactive barriers, all of which demand a thorough understanding of the underlying geochemical system. Depending on the geochemical characteristics of an aquifer, different chemical reagents can achieve varying degrees of success or even be detrimental to the remediation of the site. Advanced geochemical modeling is an invaluable tool for developing a remedy that is optimized to the site-specific geological, hydrological, and geochemical environment. In the case study presented here, …
Application Of Stable Isotopes In An Alternative Source Demonstration, Alison O'Connor
Application Of Stable Isotopes In An Alternative Source Demonstration, Alison O'Connor
World of Coal Ash Proceedings
Stable isotope analysis is commonly used in age dating, provenance studies and to differentiate between sources of groundwater. Multiple studies have shown that strontium and boron isotopic ratios can be successfully used in identifying CCR impacts to groundwater. This talk presents an applied case study using boron and strontium isotopes in conjunction with additional geochemical approaches in an alternative source demonstration. Boron and strontium isotopes were measured in both groundwater and CCR leachate over sampling events from 2019 to 2025. The data revealed that strontium and boron isotopic signatures in groundwater near the CCR unit differed significantly from both site-specific …
Distinguishing Ccp From Nuclear Impacts In Groundwater, Lea Millet
Distinguishing Ccp From Nuclear Impacts In Groundwater, Lea Millet
World of Coal Ash Proceedings
As the energy transition from fossil fuels to other generation technologies continues, many companies worldwide are evaluating the feasibility of constructing nuclear power plants at sites previously used for coal-powered generation. Thermal power plant sites offer advantages for siting nuclear generation such as proximity to cooling water and grid connections; however existing impacts to groundwater from coal combustion product (CCP) management units may confound monitoring programs designed to detect impacts from nuclear operations. For example, boron and lithium may be present in waters associated with CCP management and nuclear power plant operations, and potassium that often has concentrations above background …
Ccr Landfill Closure Challenges, Solutions And Innovation, Jay Mokotoff, Drew Browning, Steve Applegate
Ccr Landfill Closure Challenges, Solutions And Innovation, Jay Mokotoff, Drew Browning, Steve Applegate
World of Coal Ash Proceedings
CCR landfills can present unique design and construction challenges for the industry when closing these units at the end of their life. In comparison to CCR surface impoundments, CCR landfills typically have greater flexibility under the CCR Rule for operations and beneficial use purposes and may not have defined closure dates which results in some of these closures extending further into the future. However, as coal burning plants continue to shudder, the closure of these landfills is rapidly approaching. This presentation will focus on the challenging site conditions, site specific considerations and potential solutions when designing and constructing the landfill …
Engineering Granulometry To Optimize Performance Of Reclaimed Ash, Russell Hill
Engineering Granulometry To Optimize Performance Of Reclaimed Ash, Russell Hill
World of Coal Ash Proceedings
As utility production of fresh fly ash declines, the concrete industry is turning to reclaimed and beneficiated materials to maintain reliable SCM supply. This transition creates an opportunity not only to secure volumes but to engineer improved performance. The ReCinis™ beneficiation process enables this by providing controls that tune particle-size distribution (PSD), sphericity, packing behavior, surface area, and surface activation. Processing trials show that blends combining fine ground fractions with spherical, broad-graded hydrocyclone overflow (OF) materials can balance high reactivity with favorable rheology. Mechanochemical activation during grinding appears to increase reactivity beyond what surface-area metrics alone predict, likely through removal …
Alternative Cover Permitting And The Ccr Rule, Evan Andrews, Victor Damasceno
Alternative Cover Permitting And The Ccr Rule, Evan Andrews, Victor Damasceno
World of Coal Ash Proceedings
Federal rules (40 CFR Parts 9, 257 and 261) that regulate coal combustion residuals (CCR) created a significant demand associated with closure of coal ash management and storage facilities using liner systems. Timelines associated with these facility closures combined with substantial project scale and potential for future mining /reuse has driven the need for closure systems that perform beyond the prescriptive soil / geomembrane caps outlined in the federal regulations. As outlined in section 257.102 (d)(3)(i) of the CCR Rule, the standard cover system must include an infiltration layer of at least 18 inches of earthen material and an erosion …
Sustainability And Waste Diversion At Tva Shawnee "Project Phoenix", Bryan Jacob, Shane Harris
Sustainability And Waste Diversion At Tva Shawnee "Project Phoenix", Bryan Jacob, Shane Harris
World of Coal Ash Proceedings
An engineered turf closure system can serve as an ideal foundation for a solar energy system to be installed atop coal combustion residual (CCR) impoundments. This approach not only enables productive power generation during the post-closure period, it also preserves opportunities for recovery and beneficial use of CCR material in the future. “Project Phoenix” at TVA’s Shawnee Fossil Plant offers an illustrative example. This paper will cover the sustainability benefits of the companion ClosureTurf® and PowerCap® systems installed at that site as well as waste diversion activities undertaken during construction to recycle as much as practical and minimize waste destined …
Demystifying Large Language Models: How Ai Is Transforming Data, Compliance, And Decision-Making In Coal Ash And Environmental Management, Scott Pfeiffer
Demystifying Large Language Models: How Ai Is Transforming Data, Compliance, And Decision-Making In Coal Ash And Environmental Management, Scott Pfeiffer
World of Coal Ash Proceedings
The environmental and coal combustion residuals (CCR) industries generate vast amounts of information—from groundwater monitoring reports and RCRA documentation to closure plans and analytical data. Managing, interpreting, and communicating this information is a growing challenge for utilities, regulators, and consultants alike. Large Language Models (LLMs), such as OpenAI’s GPT architecture, represent a breakthrough in how organizations can interact with their technical data. These models use deep neural networks trained on billions of words to understand, summarize, and generate language with human-like accuracy. When securely adapted for enterprise use, LLMs can automate routine reporting, extract data from technical documents, generate regulatory …
Expert Perspectives On The U.S. Coal Combustion Products Market – Now, Then, And The Future, Mark Rokoff, David Cox, Walter Lemaire, John Ward
Expert Perspectives On The U.S. Coal Combustion Products Market – Now, Then, And The Future, Mark Rokoff, David Cox, Walter Lemaire, John Ward
World of Coal Ash Proceedings
This panel discussion will explore the continued evolution of the U.S. coal combustion products market, with a focus on the impacts of dynamic regulatory and market forces. Invited expert panelists will share perspectives on developments over the past several years (building on discussions from WOCA 2022 and WOCA 2024), current conditions, and expected future trends—particularly those likely to shape the market between 2026 and 2030. The discussion will address the interrelated markets for engineering, construction, and beneficiation of ash from both operating and inactive plants. Panelists will offer perspectives relevant to the full coal ash industry, from owner/operator organizations to …
Subsurface Delineation Of Coal Combustion Residuals Using Multiple Geophysical Methods, Eric Hageman, Adam Rak, Thomas Jordan, Kate Mckinley
Subsurface Delineation Of Coal Combustion Residuals Using Multiple Geophysical Methods, Eric Hageman, Adam Rak, Thomas Jordan, Kate Mckinley
World of Coal Ash Proceedings
Geophysical techniques provide alternative methods of Coal Combustion Residual (CCR) delineation and characterization to supplement more invasive boring programs used for beneficial reuse planning. A demonstration project was designed to characterize the electromagnetic and seismic stratigraphy of CCR material and test the effectiveness of three geophysical techniques: Electrical Resistivity Imaging (ERI), Transient Electromagnetic (TEM) induction, and Multi-channel Analysis of Surface Wave (MASW). The demonstration project was completed at a dry-stack CCR unit containing a variety of CCR ash, gypsum, and thin layers of drainage aggregate (limestone). During a single-day deployment, several geophysical survey tests were conducted in specific areas of …
The Cobalt Curse: Cobalt’S Role And Risks, Marley Jackowitz
The Cobalt Curse: Cobalt’S Role And Risks, Marley Jackowitz
Student Theses 2015-Present
This paper examines the hidden environmental, geopolitical, economic, and social costs of the cobalt supply chain. Fueled by the demand for battery technology and electric vehicles, cobalt has become an essential element to the green energy transition. With the largest share of global cobalt deposits, the Democratic Republic of the Congo bears a disproportionate share of the industry’s harms. Cobalt mining in the DRC is marked by environmentally degrading practices and inhumane working conditions, compromising Congolese health, safety, and well-being. Chapter 1 discusses the environmental impacts of DRC cobalt mining and its adverse effects on public health. Environmentally degrading mining …
Table Of Contents, The Editors
Machine Learning-Based Prediction And Experimental Validation Of The Pyrolysis Product Distribution In Tar-Rich Coals, Dong Shuai, Li Hongqiang, Wu Zhiqiang, Yu Zunyi, Lyu Zitao, Guo Wei, Yang Panxi, Fu Keming, Hao Xuanzhi, Liu Gen, Yang Bolun
Machine Learning-Based Prediction And Experimental Validation Of The Pyrolysis Product Distribution In Tar-Rich Coals, Dong Shuai, Li Hongqiang, Wu Zhiqiang, Yu Zunyi, Lyu Zitao, Guo Wei, Yang Panxi, Fu Keming, Hao Xuanzhi, Liu Gen, Yang Bolun
Coal Geology & Exploration
Background Tar-rich coals serve as an important coal-based oil and gas resource in China, while their pyrolysis product distribution is governed by the coupling effects of coal properties and reaction conditions. Therefore, rapidly identifying the pyrolysis product distribution patterns holds great significance for the resource evaluation and experimental design of tar-rich coals.Methods Existing studies on tar-rich coals suffer from the insufficient integration of exclusive data and limited synergistic prediction capacities for multiple products. To address these issues, this study constructed a dedicated dataset involving proximate analysis, ultimate analysis, elemental molar ratios, maceral composition, and pyrolysis conditions by systematically collecting …
Evaluation And Research Progress Of Co2 Sequestration In Deep Coal Seams, Xiong Yucan, Xu Shi’Ang, Zhang Pingsong, Lu Haifeng, Jia Yunzhong, Ge Binbin, Li Baiqiang, Liu Chang, Lei Jian, Fu Wenyu
Evaluation And Research Progress Of Co2 Sequestration In Deep Coal Seams, Xiong Yucan, Xu Shi’Ang, Zhang Pingsong, Lu Haifeng, Jia Yunzhong, Ge Binbin, Li Baiqiang, Liu Chang, Lei Jian, Fu Wenyu
Coal Geology & Exploration
Background With increasing pressure for global carbon emission reduction, geologic CO2 sequestration has emerged as a critical technical approach to achieving the goals of peak carbon dioxide emissions and carbon neutrality. Owing to their high CO2 adsorption capacity and favorable sealing conditions, deep coal seams are considered one of the most promising media for CO2 sequestration, following saline aquifers and depleted hydrocarbon reservoirs. Therefore, the exploitation and utilization of deep coal seams hold significant strategic importance for the green, low-carbon transformation of the coal industry. Methods Based on literature analysis and a review of outcomes from cutting-edge …
Mechanisms Behind The Impacts Of Co2 Concentration On Microbial Methanogenesis In Coal Seams, Wang Junyu, Liu Bingjun, Jiang Xiangqing, Chen Ruifeng, Xue Sheng, Zhou Wanlong, Yang Yundu
Mechanisms Behind The Impacts Of Co2 Concentration On Microbial Methanogenesis In Coal Seams, Wang Junyu, Liu Bingjun, Jiang Xiangqing, Chen Ruifeng, Xue Sheng, Zhou Wanlong, Yang Yundu
Coal Geology & Exploration
Background Coal seams exhibit the extensive distribution of a variety of indigenous functional microorganisms. Among these, some archaea enable methane metabolism using CO2 as a substrate, providing the potential for the biological CO2 storage and utilization in coal seams. However, conventional studies focus primarily on the degradation characteristics of coal matrix, leading to a lack of a systematic understanding of the mechanisms governing the adjustment of the methanation process in CO2-bearing environments. Methods This study investigated the bituminous coals with a high volatile content in the Huainan mining area. Using laboratory-scale experiments on methanogenesis through anaerobic …
Dynamic Prediction On Goaf Surface Subsidence For The Last Two Periods Based On The Erf Time Function, Ren Lianwei, Li Shihui, Wang Wenchang, Li Zhenhua, Chen Shaojie, Dun Zhilin
Dynamic Prediction On Goaf Surface Subsidence For The Last Two Periods Based On The Erf Time Function, Ren Lianwei, Li Shihui, Wang Wenchang, Li Zhenhua, Chen Shaojie, Dun Zhilin
Coal Geology & Exploration
Background The surface subsidence induced by coal seam mining represents a continuous dynamic evolution process. Constructing a full-time perdition model for surface subsidence in goafs holds significant theoretical and practical values for the rational utilization of land resources, the safety guarantee of engineering construction, and the transformation and development of resource-based cities. Methods To accurately predict the surface subsidence in goafs during its decline and residual periods, this study proposed a prediction model based on the error function (Erf). First, the evolution characteristics of Erf were analyzed, verifying that the subsidence, as well as its velocity and acceleration, predicted using …
Performance Optimization Of Superfine Cement Through Composite Modification Using Coal-Based Solid Waste And Modifiers, Kang Zhipeng, Luo Yong, Xiao Diancai, Ren Shuai, Cai Zhiliang, Gao Xiang, Zhang Kunzhe
Performance Optimization Of Superfine Cement Through Composite Modification Using Coal-Based Solid Waste And Modifiers, Kang Zhipeng, Luo Yong, Xiao Diancai, Ren Shuai, Cai Zhiliang, Gao Xiang, Zhang Kunzhe
Coal Geology & Exploration
Objective Superfine cement-based grouting materials generally suffer from limitations including high bleeding rates, unfavourable rheological properties, poor stability, and strength retrogression. These issues can be mitigated by incorporating modifiers, which allows for the reutilization of coal-based solid waste while enhancing the performance of composite, superfine cement-based grouting materials. Methods Superfine cement-based grouting materials with different mixing ratios were prepared by using superfine cement as the basic material, fly ash (FA) and mineral fines (MFs) as primary admixtures, and modified bentonite, methyl cellulose ether (MCE), U-type expansive agent (UEA), and magnesium oxide (MgO) as modifiers. These grouting materials and pure superfine …
Dynamic Response Characteristics And Failure Mechanism Of Coal-Rock Combination Under Different Immersion Conditions, Zhang Xiangyang, Tong Zhipeng, Duan Yungang, Yang Weikun, Chen Jianben, Xu Linfeng
Dynamic Response Characteristics And Failure Mechanism Of Coal-Rock Combination Under Different Immersion Conditions, Zhang Xiangyang, Tong Zhipeng, Duan Yungang, Yang Weikun, Chen Jianben, Xu Linfeng
Coal Geology & Exploration
Background In practical engineering, the waterproof coal pillar usually suffers from different degrees of dynamic load from the overlying strata, and its internal water distribution is non-uniform. Although the traditional “water content” index can reflect the overall water content, it is difficult to describe the non-uniform characteristics of the soaking space. Therefore, it is of great significance to clarify the dynamic failure mechanism of coal and rock mass under different immersion conditions for stability zoning control. Methods On this basis, the coal–rock combined bodies under three different forms of immersion, namely: complete immersion, unilateral immersion, and non-immersion were prepared. These …
Mine Data Fusion Technology Based On Multi-Feature Joint Decision Making, Han Shanshan, Zhang Jifeng, Fan Tao, Liu Qiang, Song Xiaojiao, Qi Zhipeng, Zheng Hangzhou
Mine Data Fusion Technology Based On Multi-Feature Joint Decision Making, Han Shanshan, Zhang Jifeng, Fan Tao, Liu Qiang, Song Xiaojiao, Qi Zhipeng, Zheng Hangzhou
Coal Geology & Exploration
Background In the field of geological exploration of coal mines, methods such as in-seam seismic exploration, the transient electromagnetic method, and audio-frequency electrical penetration offer unique technical advantages. However, each of these methods can only reflect a single physical property of a medium, suffering from limitations including the one-sidedness of information and the multiple solutions of interpretations, thus failing to adapt to the new situations of current coal mine exploration. Multi-source data fusion promotes a technological development by leaps from one-sided detection to comprehensive analysis through mechanisms of information complementation, feature enhancement, and field-source integration. Therefore, this technology can enhance …
Mechanisms Underlying Lateral Force Applied To A Pdc Cutter On A Pdc Drill Bit During Rotary Rock Breaking, Wei Jiusen, Han Xin, Liu Wei, Gao Deli
Mechanisms Underlying Lateral Force Applied To A Pdc Cutter On A Pdc Drill Bit During Rotary Rock Breaking, Wei Jiusen, Han Xin, Liu Wei, Gao Deli
Coal Geology & Exploration
Objective To improve the rock-breaking efficiency and durability of drill bits in the theoretical research on the optimal design of drill bits, the key is to systematically reveal both the rock-breaking mechanisms of polycrystalline diamond compact (PDC) cutters and the characteristics of forces applied to them. Methods Existing studies on rock breaking using a single PDC cutter generally adopt a linear or approximately linear cutting mode while neglecting the impacts of the radius of gyration. To address this issue, this study conducted experiments on cylindrical granite samples using a laboratory experimental setting for single-cutter rock breaking. With cutting depth and …
Strategic Layout And Optimization Paths Of The Standard System For The Exploration And Exploitation Of Deep Coalbed Methane, Chen Xinjun, Liu Zengqin, Shen Baojian, Zhao Shihu, Ye Jincheng, Zhang Jiaqi, Wang Tianyun
Strategic Layout And Optimization Paths Of The Standard System For The Exploration And Exploitation Of Deep Coalbed Methane, Chen Xinjun, Liu Zengqin, Shen Baojian, Zhao Shihu, Ye Jincheng, Zhang Jiaqi, Wang Tianyun
Coal Geology & Exploration
Objective In China, the deep coalbed methane (CBM) industry has emerged as a key sector for the reserve growth and production addition of natural gas. However, the current CBM technical standard system, which was developed based on shallow CBM practices, is incompatible with the demands for the exploration and development of deep CBM. To address this challenge, this study proposes the optimization paths of the current standard system, aiming to provide standardization support for large-scale exploitation of deep CBM.Methods Deep CBM reservoirs exhibit complex geological conditions of high temperature, pressure, and in-situ stress, as well as the CBM occurrence …
Parameter Optimization And Field Application Of Roof Volume Fracturing Using Horizontal Wells For Coalbed Methane Extraction From Broken-Soft Coal Seams, Zhang Qingli, Sun Siqing, Li Haozhe, Wu Xiaoxuan, Yang Fan, Zheng Yuqi, Li Wenbo
Parameter Optimization And Field Application Of Roof Volume Fracturing Using Horizontal Wells For Coalbed Methane Extraction From Broken-Soft Coal Seams, Zhang Qingli, Sun Siqing, Li Haozhe, Wu Xiaoxuan, Yang Fan, Zheng Yuqi, Li Wenbo
Coal Geology & Exploration
Objective and Method To achieve rapid coalbed methane (CBM) extraction from broken-soft coal seams using surface horizontal wells, this study proposed a volume fracturing technology for coal seam roof using horizontal wells. Focusing coal seam 4-1 in a mining area, this study established a numerical model using finite element analysis (FEA) software Abaqus Using this model, the impacts of in-situ stress on the cross-layer propagation characteristics of multiple fractures were investigated. Through true triaxial hydraulic fracturing experiments, the multi-fracture propagation patterns under varying injection rates of fracturing fluids, perforation cluster numbers, and cluster spacings were analyzed. Using 3D fracturing design …
Structural Design And Parameter Optimization Of A Vibration Absorber For Rescue Casing-While-Drilling Rigs, Liu Pu, Yao Ningping, Zou Zujie, Fan Dong, Wei Hongchao, He Binjie
Structural Design And Parameter Optimization Of A Vibration Absorber For Rescue Casing-While-Drilling Rigs, Liu Pu, Yao Ningping, Zou Zujie, Fan Dong, Wei Hongchao, He Binjie
Coal Geology & Exploration
Objective Rescue drilling rigs undergo intense vibration at borehole mouths when operating in a confined underground space of coal mines. To address this issue, this study designed a compact multi-directional, passive dynamic vibration absorber, aiming to improve the operational stability and safety of the rigs. Methods Based on the spring-mass-damping system theory, a stepwise optimization design method was proposed for the longitudinal and transverse dynamic models of the vibration absorber. For the longitudinal vibration model, the particle swarm optimization (PSO) algorithm was applied for multi-objective parameter optimization. In contrast, for the transverse vibration model, the fixed point theory was employed …
Exploring The Vertical Heterogeneity Of Extremely Thick Aquifers In Coal Mines Through Layered Fine-Scale Pumping Tests, Guo Xiaoming
Exploring The Vertical Heterogeneity Of Extremely Thick Aquifers In Coal Mines Through Layered Fine-Scale Pumping Tests, Guo Xiaoming
Coal Geology & Exploration
Objective Extremely thick aquifers in mining areas typically exhibit strong heterogeneity and high water yield. Therefore, they are prone to cause severe water inflow in mines and induce water disasters, representing a major factor affecting the mining safety of numerous mines in China. However, the vertical heterogeneity of these aquifers remains poorly understood, emerging as a primary bottleneck in the prevention and control of such water hazards. Methods To scientifically reveal the vertical heterogeneity characteristics of extremely thick aquifers, this study investigated the extremely thick Luohe Formation aquifer in a coal seam roof of a representative coal mine in the …
Optical Mechanisms Behind Vitrinite Reflectance Suppression Caused By Strong Anisotropy: A Case Study Of Contact Metamorphic Coals, An Yanfei, He Shuyang, Chen Kaixin, Gao Junhan
Optical Mechanisms Behind Vitrinite Reflectance Suppression Caused By Strong Anisotropy: A Case Study Of Contact Metamorphic Coals, An Yanfei, He Shuyang, Chen Kaixin, Gao Junhan
Coal Geology & Exploration
Objective For vitrinite with weak anisotropy, which proves uniaxial and optically negative, replacing random vitrinite reflectance (Rran) with the maximum vitrinite reflectance (Rmax) allows for the accurate correction of vitrinite reflectance suppression induced by anisotropy. However, as its anisotropy intensifies, vitrinite exhibits increasingly complex optical properties, rendering it challenging to reflect the thermal metamorphic temperature of vitrinite using Rmax. Methods This study investigated the strongly anisotropic vitrinite in coals and natural coke subjected to magma intrusion in the Shitai coal mine, Huaibei City, Anhui Province. Using a reflected-polarized light microscope (R-PLM), an …