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A Novel Model For Calculating In Situ Stress Within Deep Coal Seams Considering Microstructural Characteristics And Its Application, Zhao Haifeng, Shi Hongwei, Xie Fei, Wang Chengwang, Wang Zongfei, Chen Gaojie

Coal Geology & Exploration

Objective Research on in situ stress serves as a bridge between geological and engineering analyses. Accurate insights into in situ stress regimes are crucial for ensuring engineering efficiency and development benefits. However, microstructures are well developed in deep coal seams, for which no effective model is currently available for calculating in situ stress. Methods and Results By classifying structures into macrostructures and microstructures, this study established a novel model for calculating in situ stress in deep coal seams while considering microstructural characteristics. In the novel model, the horizontal in situ stress was decomposed into three components: the horizontal components induced …

Technique For Water-Preserved Coal Mining Based On Zonal Height Limits Along Mining Face And Mechanisms Behind Overburden Failure, Sun Xueyang, Cao Hongyi, Li Peng, Han Dehao, Luo Qiyao, Liu Kuan, Li Jihong, Yin Xu

Coal Geology & Exploration

Objective The exploitation of shallow coal seams under water bodies faces a contradiction between water resource preservation and overburden disturbance. In this case, achieving safe mining while preventing water-conducting fracture zones from affecting key aquifers and exploring techniques that place equal emphasis on water preservation and efficient resource recovery have emerged as popular research topics. Methods An integrated aquifer-overburden-coal seam model was constructed using 3D geological visualization technology. This model, combined with the principles for the setting up of waterproof coal pillars, enabled accurate delineation of zones with water inrush risks. Accordingly, a technical scheme for mining based on zonal …

Sensitivity Analysis Of Factors Influencing Water Redistribution In Vadose Zones Under Coal Mining Disturbance In Ecologically Vulnerable Areas, Wang Ao, Liu Shiliang, Wang Shanlin, Zheng Yusheng, Wang Tengye, Wang Zuzhen, Mao Deqiang

Coal Geology & Exploration

Objective Coal mining-induced disturbance leads to water redistribution in the vadose zones of mining areas. The sensitivity analysis of the factors influencing this redistribution holds critical significance for the reconstruction of eco-geological environments and the sustainable economic development in mining areas. Methods Against the engineering background of the Yushen mining area characterized by wind-blown sandy terrain in northern Shaanxi Province, this study analyzed the primary factors influencing water redistribution in the vadose zone under coal mining disturbance. Accordingly, 18 COMSOL Multiphysics numerical models for water redistribution in the vadose zone under coal mining disturbance were constructed through orthogonal experiments. Using …

Macro-Mesoscopic Developmental Patterns Of Cracks In Surrounding Rocks Of Rectangular Roadways Under True Triaxial Stresses, Shi Wenbao, Xu Qingzhao, Chang Jucai, Li Chuanming, Qiao Longquan, Miao Zhuang, Yan Aoyun

Coal Geology & Exploration

Objective and Method This study aims to investigate the relationship between the stress environment and the deformation and failure responses of surrounding rocks, thereby unraveling the inherent mechanisms underlying the deformation and failure. With cement, river sands, and gypsum as raw materials, rectangular roadway model specimens measuring 200 mm × 200 mm × 200 mm were prepared. Using a large-scale true triaxial seepage coupling testing machine, this study conducted triaxial loading tests on the rectangular roadway specimens under different lateral pressure coefficients. Using microcameras and an acoustic emission system, it monitored the whole process of the macroscopic deformation and failure, …

Simulation Of Groundwater Flow Field Evolution And Water Inrush Risks Under The Deep-Well Reinjection Of High-Tds Mine Water, Liu Qi, Sun Yajun, Fan Jianguo, Tan Xianfeng, Xiao Shengxin, Yang Chuanwei, Chen Weiyang, Chen Ge

Coal Geology & Exploration

Objective The deep-well reinjection of mine water results in a regional groundwater level rise to varying degrees, possibly inducing hydrogeological hazards such as floor water inrushes or water inrushes along faults. In this context, determining the evolutionary pattern of the groundwater flow field under long-term mine water reinjection and conducting reinjection safety assessments play a critical role in ensuring both the safety of mine water reinjection and water conservation-based coal mining.Methods This study examined the reinjection of mine water in a coal mine within the Juye coalfield, North China. Based on the geological conditions for mine water reinjection in …

An Experimental Study On The Deterioration Characteristics Of Sandstone Masses With Rock Bridges Under Cyclic Freezing And Thawing, Zhang Huimei, Li Zengle, Chen Shiguan, Yuan Chao, Zheng Shihang

Coal Geology & Exploration

Objective To determine the deformation and failure mechanisms of fractured rock masses with rock bridges in alpine regions, this study conducted mechanical property tests on rock samples with varying lengths of rock bridges subjected to cyclic freezing and thawing. Methods Through experiments, this study summarized the characteristics of the static strength deterioration of rock masses under the combined effects of different numbers of freezing and thawing cycles and varying rock bridge lengths. By combining acoustic emission signal monitoring and scanning electron microscopy, this study thoroughly explored both the evolutionary characteristics of fractures and rock rupture modes. Accordingly, it revealed the …

Current Status And Future Trend Of Research On Underground Borehole Measurement Technology For Coal Mines, Chen Long, Yang Dongdong, Li Quanxin, Chu Zhiwei, Zhang Jiguan, Chen Xiang

Coal Geology & Exploration

Background Underground borehole measurement emerges as a core technology for the safe production of coal mines. Its multi-parameter measurements, data accuracy, data transmission rate, and reliability directly influence the timeliness of early warning for disasters, the operating stability of instruments, the accuracy of borehole assessment, and the scientific rigor of intelligent decision-making under complex deep geological conditions. Advances So far, the measurement while drilling (MWD) and post-drilling borehole visualization techniques have developed into a diversified technological system. Specifically, the MWD technique has achieved a leap from wireline to wireless transmission, obviating the reliance on wireline drill rods in traditional measurement …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Environmental Risk Assessment Of Co2 Storage Combined With The Overlying Coal Mining, Gu Leiyu, Li Wenhui, Huang Wei, Zhou Quanchao, Zhu Yalong, Li Xiaying, Liu Guizhen, Li Qi

Coal Geology & Exploration

Objective Carbon capture, utilization, and storage (CCUS) technology serves as a key method for carbon neutrality. However, large-scale engineering applications of CCUS are still confronted with serious challenges of environmental risks. Therefore, systematic environmental risk assessment plays an essential role in ensuring the environmental safety and social acceptability of CO₂ geological storage projects. Methods Targeting the CO₂ geological storage project combined with overlying coal mining in Zhengning County, Gansu Province, this study performed the environmental risk assessment of CO₂ leakage based on the requirements of the Technical Guideline on Environmental Risk Assessment for Carbon Dioxide Capture, Utilization, …

Variation Characteristics Of Co2 Adsorption Phase Density In Coal Seam And Its Controlling Mechanism: A Case Study Of Huainan-Huaibei Coalfield, Liu Huihu, Fan Zhengpu, Yang Jinghao, Liu Junlin, Ding Hai, Xu Hongjie, Gao Deyi, Fang Huihuang, Zhao Yuqing

Coal Geology & Exploration

Objectives and Methods The CO₂ adsorption phase density is a key factor determining the CO₂ adsorption sequestration capacity in coal seams. To deeply understand the characteristics of CO₂ density distribution in pores of the coal seam, taking the No.13 coal from Liuzhuang Mine of Huainan mining area and the No.7 coal in Huaibei mining area as the research objects, the CO₂ adsorption phase density of at different pressures and temperatures with different dominant pore diameters was simulated through the simplified local density theory (SLD). The CO₂ adsorption phase densities were obtained by different methods, the …

Reservoir Responses To Reactions In Co2 Mineral Trapping And Geologic Carbon Sequestration Prospects For Basalts In Western Guizhou Province, China, Han Sijie, Ai Zhixi, Liu Jijie, Zhou Xiaozhi, Gao Wei, Liu Zhu

Coal Geology & Exploration

Background Geologic CO₂ sequestration in basalts has attracted wide attention in recent years owing to its safe, stable, and efficient CO₂ trapping mechanisms.Methods Focusing on basalts in the Longtan Formation within western Guizhou Province, China, this study simulated the CO₂-water-basalt geochemical reactions under varying temperatures, pressures, and times. Through tests and comparison of mineralogy, geochemistry, and reservoir physical properties before and after the reactions, this study investigated the factors influencing the reactions and elucidated the post-reaction co-evolution mechanism between minerals and pores. Furthermore, the mechanisms behind CO₂ trapping in basalts were summarized, and the …

Spatial Distribution And Source-Sink Matching Of Stationary Co2 Emissions In Zhejiang Province, Zhu Qianlin, Chen Dongbao, Liu Hanxiao, Lu Shijian, Chen Fu

Coal Geology & Exploration

Objective Carbon capture, utilization, and storage (CCUS) is supposed to become an essential technology for the consumption of fossil fuels under the background of achieving carbon neutrality. Delving into the spatial distribution of regional CO₂ stationary sources and the source-sink matching characteristics will contribute to more rational decision-making in CCUS deployment and promote the development of carbon sequestration technology. Methods This study investigated the spatial distribution of CO₂ stationary sources in Zhejiang Province and, using the carbon emission factor method, assessed their CO₂ emissions based on their scales. Furthermore, it analyzed the geological features of both onshore …

Supersaturation Effect And Its Characterization In Gas-Rich Intervals Of Deep Coal Seams, Zhou Lihong, Li Yong, Ding Rong, Li Yun, Li Yongzhou, Kong Jintao

Coal Geology & Exploration

Objective and Method High free gas content serves as a key factor controlling the enrichment and high productivity of deep coalbed methane (CBM). However, its direct determination is challenging, making the accurate identification of free gas-rich coal seam intervals a core scientific issue for efficient exploration and recovery of CBM. This study investigated the Daning-Jixian block (also referred to as the Daji Block) within the Ordos Basin. Based on analyses and tests of the gas content, coal macrolithotype, physical properties, and log responses of cores collected from representative wells through pressure-retained coring, this study systematically assessed the vertical heterogeneity of …

Physical Simulation Experiments On 4d Visualization Of Dynamic Methane Diffusion And Adsorption In Low-Porosity And Low-Permeability Coals, Liu Tong, Jiao Baizhuo, Lin Baiquan, Sang Shuxun, Yang Wei, Liu Shiqi, Liu Ting, Li He, Yang Mingxing

Coal Geology & Exploration

Objective and Method The diffusivity of methane (CH₄) in coal seams significantly influences the surface extraction of coalbed methane (CBM) and underground gas drainage. However, the visualized characterization of the diffusion and migration processes of CH₄ in coals remains challenging. To address this issue, this study systematically demonstrated the similarity between krypton (Kr) and CH₄ in their adsorption and diffusion behavior in coals. Utilizing Kr—a gas with high X-ray attenuation—as a tracer substitute for CH₄, this study achieved the transparent observation of the dynamic gas migration process in low-porosity, low-permeability, and heterogeneous coals using …

Organically-Bound Forms Of Alkali And Alkaline Earth Metals In High-Alkali Coals And Their Geological Indications, Wang Xiaoling, Wang Shaoqing, Zhao Yungang, Mu Ruifeng, Shao Yan

Coal Geology & Exploration

Objective and Method Alkali and alkaline earth metals (AAEMs) in coals adversely affect coal processing and utilization. Among the AAEMs, water-soluble and mineral-hosted metals can be largely removed through water washing, flotation, and heavy liquid separation, while organically-bound AAEMs are difficult to eliminate. In this study, high-alkali coal samples with varying vitrinite/inertinite ratios (V/Is) collected from the Zhundong coalfield in Xinjiang were selected to investigate the organically-bound forms of AAEMs. Through sequential chemical extraction, combined with experimental techniques such as ²³Na cross-polarization magic-angle spinning nuclear magnetic resonance (²³Na CP/MAS NMR) and transmission electron microscopy-energy dispersive …

Mechanisms Underlying Sodium Enrichment In Coals In The Dananhu Mining Area, Turpan-Hami Basin, Qi Zhenghui, Sun Fanxing, Wang Wenlong, Huang Chunhui, Liang Kaihua, Huang Yangyang, Shao Longyi

Coal Geology & Exploration

Background The Dananhu mining area boasts abundant coal resources, serving as a significant coal-fired power generation base in Xinjiang, China. However, the high sodium (Na) content in coals within the mining area tends to cause fouling and slagging during coal combustion, severely affecting the clean and efficient utilization of coal resources in the area. Methods and Results epresentative samples collected from the major mineable coal seams were subjected to proximate and ash-composition analyses. The analytical results show that the coal samples had low ash and sulfur contents and high volatile content. SiO₂ predominated in the ash components, followed by …

Mechanisms Behind Soil Water Evaporation And Infiltration During Long-Term Microbial Reclamation In Coal Mining-Induced Subsidence Areas In Northern Shaanxi Province, China, Ke Zengming, Bi Yinli, Yang Wei

Coal Geology & Exploration

Background Water scarcity is identified as an important factor restricting ecological restoration in arid and semi-arid mining areas. The application of microbial reclamation technologies, especially inoculation with Arbuscular mycorrhizal fungi (AMF), has achieved encouraging ecological effects in mining areas. In this case, investigating soil water movement and its controlling factors in mining areas undergoing long-term microbial reclamation is a key scientific issue for understanding the long-term ecological restoration mechanisms of AMF. Methods This study investigated the microbial reclamation base in the coal mining-induced subsidence area of the Daliuta coal mine of northern Shaanxi Province, located in the middle reaches of …

Water Quality Characteristics And Reutilization Of Goaf Water From Shallow Coal Seams Within The Datong Mining Area, Shanxi Province, China, Li Jun, Gui Herong, Ding Pengfei, Chen Yongqing, Wan Heyong, Li Weiqi, Huang Dawei, Peng Weihua, Hu Yang, Guo Yan

Coal Geology & Exploration

Objective The Datong mining area in Shanxi Province of China faces serious threats from goaf water hazards, while the goaf water drainage is constrained by environmental protection policies. Therefore, the reutilization of goaf water serves as an effective approach to eliminating mine water hazards, protecting water environments, and mitigating water scarcity in the mining area. Methods This study investigated goaf water from shallow coal seams in the Datong mining area. Based on water quality assessment theories and a range of hydrogeochemical indices, including saturation index (SI), chloro-alkaline index (CAI), and sodium adsorption ratio (SAR), this study conducted a joint determination …

An Experimental Study On The Selection Of Slow-Release Carbon Source Materials For Sulfate-Reducing Bacteria-Based Remediation Of High-Sulfate Mine Water In Coal Mines, Xiahou Ming’An, Zhang Li, Xu Zhimin, Guo Juan, Chen Ge, Xiong Xiaofeng, Sun Yajun

Coal Geology & Exploration

Background High-sulfate mine water poses a major aquatic environmental challenge in coal mining areas across China. Accordingly, the cost-effective and efficient treatment of such water has become an urgent need for the sustainable development of the mining industry. Despite its considerable promise, microbial remediation based on sulfate-reducing bacteria (SRB) shows limited efficiency due to the scarcity of dissolved organic carbon (DOC) in mine water.Methods The application of external slow-release carbon source (SRC) materials for SRB faces a range of challenges, such as the potentially excessive release of organic carbon in the initial stage, the unclear release mechanisms of dissolved …

Failure Mechanisms And Energy Dissipation Characteristics Of Anchorage Bodies Under Dynamic Loading, Wang Changcheng, Yang Ke, Liu Wenjie, Zhang Zhainan, Zheng Shizhang, Xu Rijie, Guo Penghui

Coal Geology & Exploration

Objective Under intense mining in deep parts of coal mines, the roadway support systems are significantly affected by both far- and near-field dynamic loads, accompanied by the strong deformations of the surrounding rocks. Therefore, investigating the failure mechanisms of anchorage bodies under dynamic loading becomes particularly important. Methods Using the split Hopkinson pressure bar (SHPB) test system and digital image correlation (DIC) technology, the study investigated the mechanical response characteristics of the anchorage bodies under different impact air pressures. Accordingly, it determined dynamic stress-strain relationships, energy dissipation characteristics, cracks’ evolutionary patterns, and failure modes of anchorage bodies. Results and Conclusions …

Advances In Research And Future Prospects Of Borehole Geophysical Prospecting Technology For Coal Mines, Li Ping, Wei Rong, Fan Tao, Zhao Rui, Jiang Bici, Tian Xiaochao, Wang Bingchun

Coal Geology & Exploration

Background Borehole geophysical prospecting technology for coal mines integrates the advantages of both drilling and geophysical prospecting. Accordingly, multiple critical advances have been achieved in its applications to the technologies and equipment for intelligent coal mining in recent years, enabling long-distance, relatively high-precision geological exploration. This technology plays an increasingly important role in a range of fields, including deep mineral resource exploration and the reconnaissance surveys of hidden disaster-causing factors, providing robust support for safe and efficient coal mining. Advances This study systematically reviews the development history of borehole geophysical prospecting technology, elaborating advances in research on the methodology, theories, …

Developing A Waste-To-Energy Assessment Framework Integrating Engineering And Policy Dimensions Using A Triple Bottom Line Approach, Izech Brian O. Edwin, King Harold A. Recto

Electronics, Computer, and Communications Engineering Faculty Publications

The management of municipal solid waste (MSW) in swiftly urbanizing Philippine cities has emerged as a critical concern in both energy and governance. Dependence on landfills is approaching critical thresholds as disposal sites near saturation, transportation costs escalate, and host communities increasingly resist garbage transfers. In response, this study proposes a comprehensive Waste-to-Energy (WtE) assessment framework that integrates engineering evaluation with policy and stakeholder analysis to support sustainable decision- making.

Using Baguio City as a case study, the framework applies a Triple Bottom Line (TBL) approach to evaluate three waste management scenarios: (1) current landfill-dominated practices, (2) engineered landfill with …

The Price Of Priorities: How Human Choices Fuel Climate And Ecological Decline, Keisha Hickman

Biological Sciences Undergraduate Honors Theses

This thesis examines the ways in which human priorities and behaviors contribute to the escalating climate crisis and ecological systems. We will first analyze the role of social media in shaping public discourse on climate change and critically evaluate the priorities of institutions that have the means to assist in wildlife conservation. Both speak to the current behaviors of humankind prioritizing their own entertainment over meaningful efforts to mitigate climate change and preserve biodiversity. We will then shift to exploring the profound impact of human population growth and its associated activities on other species and ecosystems. Finally, the thesis will …

An Integrated Modeling Framework To Evaluate Circularity Of The Corn–Water–Ethanol–Beef Nexus, Heydi Han

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation examines the transition from conventional linear agricultural and food bioenergy systems toward more circular, resilient, and resource-efficient configurations. Prior research indicates that spatial and temporal variability in soil, weather, animal biological responses, and management decisions strongly influences productivity, nutrient-use efficiency, and profitability. Studies have also shown that a diversified circular system can buffer these sources of variability, improving stability and adaptive capacity. Building on these insights, the central focus of this work is to develop an integrated modeling framework to evaluate circularity within the Corn-Water-Ethanol-Beef (CWEB) nexus and explore how climate variability and management choices shape system-wide performance. …

Piezoelectric Energy Harvesting From Roadways: Challenges, Advances, And Future Directions, Heba Gaber, Mohamed Abdelraheem

Faculty Publications

As the global demand for renewable energy intensifies, piezoelectric energy harvesting from roadways has emerged as a promising avenue for sustainable power generation. This systematic literature review analyzes 61 peer-reviewed studies to assess the feasibility, performance, and potential of integrating piezoelectric systems into roadway infrastructure. While technology faces challenges, such as high installation costs, limited energy output, and a scarcity of thorough economic evaluations, findings suggest it holds considerable promise as a supplementary renewable energy source. The review analyzes the operational characteristics and efficiencies of various piezoelectric transducers, identifies key factors influencing system performance, and evaluates recent technological advances. It …

Data-Driven Evaluation Of Sustainable Waste-To-Energy Pathways For Intelligent Urban Systems, Izech Brian O. Edwin, King Harold A. Recto

Electronics, Computer, and Communications Engineering Faculty Publications

The handling of municipal solid waste (MSW) in swiftly urbanizing Philippine cities poses intricate energy and governance challenges. In Baguio City, reliance on landfills has reached critical levels due to diminishing capacity, rising transport costs, and opposition to trash transfers by nearby LGUs. Although shaped by unique topographical and governance constraints, Baguio’s situation reflects issues faced by other rapidly growing Philippine cities; therefore, analyzing it offers insights for national MSW decision-making. This study applies a triple bottom line (TBL) framework to assess three management scenarios: (1) Status Quo, where all MSW is landfilled with no energy recovery; (2) Landfill with …

Ai-Based Mapping Of Offshore Wind Energy Around The Korean Peninsula Using Sentinel-1 Sar And Numerical Weather Prediction Data, Jason Sung-Uk Joh, Son V. Nghiem, Menas Kafatos, Jay Liu, Jinsoo Kim, Seung Hee Kim

Institute for ECHO Articles and Research

Offshore wind farm projects are being promoted in the seas surrounding the Korean Peninsula to secure renewable energy. To support site selection, offshore wind resource maps were generated using deep neural networks trained on Sentinel-1 SAR imagery, numerical weather prediction data, offshore wind observations, sea surface temperature, and bathymetry. The deep neural network (DNN) framework consisted of six sub-models targeting eastward and northward wind components across three regions—the Yellow Sea, Korea Strait, and East Sea—to account for spatial heterogeneity. The proposed models outperformed existing approaches, achieving mean absolute errors (MAE) ranging from 1.31 to 1.69 m/s and correlation coefficients (CC) …

Coal Phase-Out In The Silesian Coal Regions – Building Sustainable Scenario On Past Experiences, Adam Drobniak, Jan Bondaruk, Mirosław Skibski

Journal of Sustainable Mining

The dynamics of phasing out of hard coal mining are currently the subject of many debates and policies programming the energy transition. Diversity of opinions on the speed of the hard coal mining transition is evident. This discourse uses a number of technical, environmental, economic and social arguments that are not always supported by evidence-based analyses. As assumed in the European Green Deal, a responsible approach to decarbonisation requires just transition values. Thus, the negative effects of mining phasing out should be well recognized to enable their mitigation. This applies especially to the Silesian Voivodeship, where the concentration of so-called …

Response Characteristics Of Vegetation Ecology And Land Use Changes Tocoal Mining In Semi-Arid Regions, Du Zhen, Zhang Maosheng, Yun Shaoqi, Sun Pingping, Feng Li

Coal Geology & Exploration

Objective In semi-arid regions, intensive coal mining is prone to induce vegetation degradation and reshape the land use pattern. To identify the ecological impacts of coal mining and provide support for differential restoration, this study presents a quantitative comparison of changes in vegetation, soil moisture content, and land use types between mining-affected and non-mining areas.Methods Yulin City, Shaanxi Province was investigated in this study. Two parallel baseline frameworks were constructed: mining-affected and non-mining areas, which were compared under the sandy-fluvial terrace and loess hilly-gully landforms. The annual maximum normalized difference vegetation index (NDVI) derived from Landsat imagery was used …

Water Immersion-Induced Damage Mechanisms And Enhancement Via Nano-Modification For Artificial Dam Specimens With Vertical Interfaces, Li Yijia, Hao Xianjie, Chen Yuguang, Pang Tian, Yang Huaixiang, Li Hang, Ji Jinyi, Li Xinyu

Coal Geology & Exploration

Objective To accelerate ecological protection and high-quality development in the Yellow River basin, the concept of “conductivity, storage, and utilization” has been proposed to achieve the mine water storage and protection by transforming goafs into underground reservoirs and utilizing waterproof concrete dams. However, under the action of long-term water immersion and mining activity, the interfaces of composite concrete dam structures might undergo strength degradation, leading to hidden hazards. Methods By incorporating 0.5% and 1.0% nano-SiO₂, -Al₂O₃, and -TiO₂, this study prepared specimens with one vertical interface each that comprised double semi-cylinders through …