Sustainability Commons^™

3d Advanced Geological Prediction Based On Reflected Seismic Waves And Its Application Effects, Cai Sheng

Coal Geology & Exploration

Objective For the advance geological prediction of tunnels based on reflected seismic waves, the traditional 2D observation method tends to cause spatial positioning deviations of anomalies. To overcome this limitation, this study developed a 3D seismic wave-based advance geological prediction method according to the actual geometries of tunnels. Methods Using the technical path consisting of theoretical analysis, numerical simulation, and engineering verification, this study solved key technical challenges including 3D wavefield reconstruction, spatial modeling, and migration imaging in the 3D detection system. Based on the principle of geometric seismology, this study demonstrated the enhancement effects of 3D observation on the …

A Time Series Forecasting Model Integrating Spatial Features For Inter-Borehole Resistivity And Its Application, Wang Jianghong, Liu Shuo, Wang Gang, Xue Wuqiang, Li Bofan

Coal Geology & Exploration

Background Mine resistivity prediction serves as a core technique for water hazards monitoring in coal mines. However, due to sparse monitoring points and insufficient spatial resolution, conventional prediction approaches fail to capture dynamic resistivity variations under complex geological conditions.Objective and Methods To address this challenge, this study developed a deep learning-based time series forecasting model integrating spatial features for inter-borehole resistivity. Using a prediction framework constructed based on long short-term memory (LSTM) and critical spatial monitoring points selected through Pearson correlation analysis, this model (also referred to as the LSTM model) enabled high-precision prediction of resistivity in unknown areas. …

Parameter Characteristics And Rock-Breaking Mechanisms Of Horizontal Drilling Of Underground Collapsed Bodies In Coal Mines, Yao Ningping, Dou Xuqian, Han Zhaoyang, Zhang Guohua, Sun Yuchen, Li Hao, Wang Li

Coal Geology & Exploration

Objective With continuously increasing coal mining depth, the risks of hazards such as roof collapse and personnel entrapment caused by high in situ stress and mining-induced pressure have significantly intensified. Drilling emerges as a key means of rapidly establishing rescue passageways. However, the drilling process tends to face multiple challenges, including complex geological structures, unstable collapsed bodies, and low drilling efficiency. Methods This study aims to reveal the rock-breaking mechanisms during the drilling of collapsed bodies, optimize drilling parameters to ensure reliable borehole formation, and achieve efficient drilling of collapsed bodies. To this end, this study developed a large-scale experimental …

A Design Method For Timeliness Optimization Of The Round-Trip Actuating Mechanisms Of Rescue Vehicle-Mounted Drilling Rigs, Cao Chao, Mao Bingquan, Zhang Zhonghai, Chang Renqi, Zhao Jiyun, Han Jing, Huang Di

Coal Geology & Exploration

Objective In the field of mine accident rescue, creating vertical rescue channels through surface drilling operations using a rescue vehicle-mounted drilling rig (RVMDR) proves the most effective. However, the limitation of the vehicle’s load capacity necessitates balancing the driving speeds and stability of the round-trip actuating mechanisms. Furthermore, establishing an optimization design and configuration system of parameters to maximize the operational capacities of these actuating mechanisms plays a key role in ensuring rescue efficiency. Methods By establishing a multiple spatiotemporal planning model for the round-trip actuating mechanisms of the RVMDR, this study determined the value ranges and design processes of …

Well Spacing Optimization Technology For Coalbed Methane Horizontal Wells, Wang Yuting, Yang Yanhui, Zhang Cong, Wang Xiuwei, Liu Zhong, Chen Jiale, Dong Qing, Sun Tao, Zhang Wuchang, Li Kexin, Wang Qi

Coal Geology & Exploration

Background Well spacing design directly affects the resource utilization and exploitation benefits of blocks. Rational well spacing design plays a significant role in the commercial exploitation of coalbed methane (CBM) fields. Since the beginning of China’s 14th Five-Year Plan, blocks for CBM production in the southern Qinshui Basin have experienced a gradual increase in burial depth, a progressive decline in permeability, and a constant update of primary exploitation technology. Consequently, traditional well spacings fail to meet the requirements for field CBM exploitation any longer. Methods This study investigated the western Qinnan – eastern Mabi block by combining numerical simulations with …

Geochemical Characteristics And Genesis Of Element Enrichment Of Niobium-Rich-Rare Earth Metal Layer In Longtan Formation Of Zhina Coalfield, Ding Yunlong, Wang Fangfa, Li Bi, Tang Lifang, Yang Yi, Li Shangyuan, Wang Xiaofang, Zou Yinhong, Wang Yang

Coal Geology & Exploration

Background With the increasing demand for strategic metals and the gradual depletion of traditional metal deposit resources, coal and coal-bearing rock series are considered to be potential sources of rare metals, and coal series associated has become one of the main directions of current mineral exploration. A set of coal measure strata rich in niobium (Nb) and rare earth elements (REE) has been found in Zhina coalfield, western Guizhou and the contents of Nb and REE are as high as 334.89 μg/g and 1014.51 μg/g, respectively. This discovery is of great significance to the theoretical study of coal measure metal …

Advances In Research On The Activation And Recovery Of Strategic And Critical Valuable Metals From Coal Fly Ash, Wang Yuhao, Dong Zhongbing

Coal Geology & Exploration

Background Coal fly ash, a bulk solid waste byproduct from coal-fired power generation, has a global annual output exceeding 0.75 billion tons. Its disordered piling poses severe environmental risks, such as the generation of heavy metal leachate and PM_2.5 emissions. However, coal fly ash is rich in aluminum (Al 100‒200 mg/g), gallium (Ga 10‒300 μg/g), lithium (Li 1 300‒3 700 μg/g), and rare earth elements (REEs 200‒800 μg/g), establishing it as a potential alternative resource of strategic metals. Methods By analyzing the current domestic and international technologies for metal recovery from coal fly ash, this study expatiates on the …

Hybrid Differentiator-Based Method For Estimating The Drilling Speed Of A Vehicle-Mounted Drilling Rig During Surface Drilling For Mine Rescue, Wang Yunfei, Zhao Jiyun, Hu Yongjie, Zhang Zongyang, Pan Xiaochen

Coal Geology & Exploration

Background Vehicle-mounted drilling rigs (VMDRs), key devices in surface drilling for mine rescue, directly connect the ground and underground disaster-hit areas through vertical drilling, thereby creating rescue channels for trapped people. In this case, the drilling speed of VMDRs serves as an important indicator for evaluating surface drilling operations. However, directly determining the drilling speed is challenging due to the limitations of position sensors. Methods This study developed an estimation method based on a new hybrid differentiator (NHD), allowing the drilling speed to be calculated using measurable displacement signals. First, a continuous switching function was devised, and its convergence characteristics …

Methodology And Integration For Dynamic Safety Assessment And Early Warning Of Drilling Sites For Emergency Rescue After Underground Space Collapse, Xie Zhongzhi, Zhang Guohua, Wei Xingtong, Zhang Ning, Wang Xiaotian, Ni Xiaoyang, Zhou Zhengwen, Wang Xianze

Coal Geology & Exploration

Objective IGiven the lack of methods for dynamic safety assessment related to disasters in drilling site environments for emergency rescue after underground space collapse, this study proposed a multisource data-driven methodology for dynamic safety assessment and real-time early warning. Methods By comprehensively considering the disaster-inducing environment and disaster-causing factors at drilling sites for emergency rescue, this study established the safety assessment indices of the environment and their grading system. By integrating multi-source data on surrounding rock deformation, gas concentration, and drilling rig vibration, this study developed a safety assessment method through combination weighting achieved using the analytic hierarchy process (AHP) …

Digital Rock Modeling And Elastic Simulations Of Fractured-Vuggy Carbonate Reservoirs, Zhu Wei, Zhao Luanxiao, Wang Yirong

Coal Geology & Exploration

Objective The Tarim Basin exhibits extensively distributed deep fractured-vuggy carbonate reservoirs. Therefore, determining the seismic and petrophysical characteristics of carbonate reservoirs with a fracture and vug system will provide significant guidance for the exploration, discovery, drilling, and exploitation of favorable reservoirs in the basin. Variations in the filling state of dissolution fractures and vugs will lead to significantly different elastic and attenuation characteristics of the reservoirs. Methods Based on geological insights into the geometric structural and filling characteristics of the dissolution fracture-vug system in the outcrop sections of carbonate strata in the Tarim Basin, this study proposed a digital rock …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Fracturing Evolution Mechanisms Of Eroded Coals Under The Temperature Effect Of The Co2-H2O System, Lin Baiquan, Shi Yu, Liu Ting, Shen Yang, Huang Tao

Coal Geology & Exploration

Background Injecting hot flue gas produced and discharged by gas-fired power plants into deep coal seams where gas is difficult to extract enjoys dual benefits: gas production growth and geologic CO₂ sequestration. However, there is an urgent need to determine the impact of the heat-carrying property of hot flue gas on the stability of coal reservoirs. To address this issue, the key is to clarify the fracturing evolution mechanisms of eroded coals under the temperature effect of the CO₂-H₂O system.Methods Using the independently built platform of CO₂-H₂O-coal interactions that consider …

Advances In Research On Geological Evaluation Of Compressed Air Energy Storage In Underground Gas Storage Facilities, Jiang Wen, Huang Leqing, Zhang Songhang, Ma Huiying

Coal Geology & Exploration

Background Against the backdrop of achieving peak carbon dioxide emissions and carbon neutrality globally, renewable energy has developed rapidly and is gradually changing the world's energy mix. However, the intermittent and fluctuating nature of photovoltaic and wind power energy is prone to cause grid frequency fluctuations and reduced power supply reliability. Compressed air energy storage (CAES) technology has emerged as the key to the stable operation of the green power grid thanks to its large capacity and low cost.Methods Based on a systematic review of domestic and international literature in recent years, this study organizes the current theoretical and …

Macroscopic Failure Characteristics And Seepage Pattern Of Damaged Goaf-Side Coal Pillars Under Confined Water Accumulation, Liu Weitao, Chen Dongqi, Liu Yuben, Du Yanhui, Zhao Jiyuan

Coal Geology & Exploration

Background The method of supporting roadways using small coal pillars has been widely applied in China. As a result, the stability of goaf-side coal pillars affects mining safety. Resulting from multiple disturbance effects, coal pillars tend to contain various types of damage fractures. The confined water environment in goaves with water accumulation might cause the instability failure of damaged goaf-side coal pillars. Methods To investigate the impacts of the damage fracture structure on coal stability, this study introduced the concept of relatively stable initial damage fractures. Based on the theory of damage mechanics, this study constructed hydro-mechanical-damage (HMD) coupling models …

Pseudo-2d Mt Inversion Technique For Small-Frame Tem And Its Application In Advance Geological Prediction, Han Ziqiang, Wanma Longzhi, Li Xiangfeng, Yang Yongqiang, Zhu Xiaoming, Luo Chengxian, Tang Li

Coal Geology & Exploration

Objective To address the bottlenecks of low computational efficiency and impracticality of multi-dimensional inversion in the advance geological prediction based on the transient electromagnetic method (TEM), this study developed a pseudo-two-dimensional (2D) magnetotelluric (MT) inversion technique for small-frame TEM based on time-frequency transformation. Methods First, this study corroborated the significant similarity between the late-time apparent resistivity derived using small-frame TEM and the Cagniard apparent resistivity in the MT method under the parameters commonly used in advance geological prediction. Then, the optimal time-frequency transformation coefficient (C_TF) was introduced to achieve a rapid conversion from the late-time apparent resistivity …

Life Cycle Assessment Of The Cultivation Of Lettuce In A Hydroponic System Using The Nutrient Film Technique, Raquel Jordan

All Theses

Hydroponic systems are an emerging method of soilless crop cultivation typically done inside a greenhouse where nutrients are delivered dissolved in water rather than being supplied from the soil. Potential benefits of hydroponic systems include reduced irrigation requirements, higher crop yield per area, and the ability to grow crops year-round in nontraditional areas such as urban settings, cold climates, and sites with contaminated soil. However, hydroponic systems tend to have high energy requirements for lighting and climate control, which can yield significant environmental impacts. To explore the environmental impacts of cultivating lettuce in a nutrient film technique (NFT) hydroponic system, …

Development And Evaluation Of Supported Ionic Liquid Membrane And Porphyrin Frameworks For Carbon Capture Separation, Sarang Ismail

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

The global urgency to mitigate anthropogenic CO₂ emissions has intensified the pursuit of energy-efficient separation technologies. Supported Ionic Liquid Membranes (SILMs) have emerged as promising candidates for CO₂ capture due to their tunable solubility-selectivity and low energy requirements. However, challenges such as mechanical instability, limited scalability, and trade-offs in transport performance have impeded their widespread adoption.

This thesis explores a systematic approach to designing and optimizing SILMs for enhanced CO₂ separation by tailoring polymer–ionic liquid interactions, processing conditions, and material architectures. A comprehensive set of studies were conducted using poly(vinylidene fluoride) (PVDF) with varying molecular weights, different grades of PEBAX®, …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Key Technologies And Approaches For Water Resource Conservation And Utilization In Arid To Semi-Arid Open-Pit Coal Mining Areas In The Northern Sand Prevention Belt Of China, Fang Jie, Xu Zhimin, Cheng Wei, Lu Zihan, Zhao Yongqiang, Zhu Yuhao, Chen Tianci

Coal Geology & Exploration

Background The northern sand prevention belt (NSPB) of China is primarily distributed in arid and semi-arid regions such as Xinjiang, Inner Mongolia, Ningxia, and Gansu. This belt exhibits scarce rainfall and intense evaporation, which lead to a shortage of water resources and vulnerable ecosystems. In recent years, the large-scale development of open-pit coal mines has caused increasingly violent mining disturbance in this belt, as well as increasingly prominent issues such as a decline in regional groundwater levels and ecological contradictions. To address technical challenges in balancing coal exploitation and water resource conservation in this belt, there is an urgent need …

Trace Element Migration In Groundwater In Sandstone Aquifers In The Jurassic Coalfields: A Case Study Of The Guojiahe Coal Mine, Shi Longqing, Qu Xingyue, Cheng Hao

Coal Geology & Exploration

Background The Ordos Basin, a vital energy hub in China, contains considerable coal reserves. However, the environmental issues arising from coal mining warrant attention, especially given the fragile ecosystems of the Jurassic coalfields. Methods This study investigated the Guojiahe Coal Mine in Shaanxi Province. Based on measured concentrations of 31 trace elements dissolved in sandstone aquifers across varying geological ages, this study conducted a comparative analysis of the evolutionary characteristics of these trace elements between unmined reducing and post-mining oxidizing conditions using numerical simulations. Accordingly, it revealed the impacts of coal seam mining on trace element migration in groundwater in …

Seismic Anisotropy Of Sandstone Aquifers In Coal Seam Roofs, Yu Hang, Chen Tongjun

Coal Geology & Exploration

Objective The identification and assessment of sandstone aquifers in coal seam roofs play a vital role in the safe mining of mines. Investigating the rock physics and amplitude variation with incidence and azimuth (AVAz) responses of these sandstone aquifers is critical to the prevention and control of water hazards in mines. Methods By integrating rock physical models Voigt-Reuss-Hill (VRH), differential equivalent medium (DEM), Hudson, and Wood, as well as Gassmann’s anisotropic fluid substitution theory, this study proposed a rock physics modeling method for fractured sandstones of the horizontal transversely isotropic (HTI) media type (hereafter referred to as HTI sandstones). Using …

Research On Monitoring And Early Warning Systems For Mine Water: Progress And Prospects, Yin Shangxian, Ding Yingying, Lian Huiqing, Dong Donglin, Du Tong, Yin Huichao, Zhao Peng, Zhang Yi’An, Wang Xiong

Coal Geology & Exploration

Background Water disasters in mines are occasional accidents occurring due to the influence or triggered by mining-induced intense changes in geological bodies. The complexity, heterogeneity, and dynamics of geological bodies, coupled with the random and instantaneous nature of mining influence, lead to the uncertainty, instability, occasionality, and transience of water disasters in mines. Given that mine water monitoring and early warning serve as a prerequisite for advanced disaster prevention and control, their research and system construction hold great theoretical significance and practical value. Progress and Prospects Fighting against water disasters in mines is conducted throughout the development and utilization of …

Experiments On The Diffusion Patterns Of Coal Gangue-Based Grout In Goaves Under Varying Rock Particle Sizes And Grout Mass Fractions, Zeng Yifan, Yuan Zilong, Li Hao, Wu Qiang, Zhao Gangyi, Zhou Anqi, Gao Xiang, Zhang Shuai, Bai Yanfei, Liang Jin, Yang Huxiong, Sheng Xinli, Yang Donghui, Zhao Yixia

Coal Geology & Exploration

Objective Investigating grout diffusion patterns and predicting the grouting range hold great significance for coal gangue grouting and filling engineering in goaves. Specifically, they are significant for designing grouting hole and row spacing, guiding grouting construction, determining the grouting filling degree, and further ensuring grouting effects. Methods Using crushed rocks as the medium to be grouted and coal gangue-based grout as the grouting materials, this study conducted grouting experiments under different particle sizes of crushed rocks and varying mass fractions of grout. Accordingly, it investigated the flow patterns of gangue-based grout in goaves. Results and Discussion Under a mass fraction …

Differential Roof Water Hazards And Comprehensive Utilization Of Mine Water In The Dongsheng Coalfield, Huang Haiyu, Ding Xiang, Liu Xi, Fan Jiangwei, Ji Zhuochen, Li Zhaoyang

Coal Geology & Exploration

Objective The Dongsheng coalfield exhibits various types of mine water hazards, complex water filling mechanisms, and high water inflow with high total dissolved solids (TDS) content in mining areas. These characteristics pose challenges to the comprehensive utilization of mine water, severely restricting the safe, green, and efficient coal mining in the coalfield. Methods This study aims to reveal the roof water filling characteristics of the Dongsheng coalfield and enhance the comprehensive utilization of mine water. Using methods including statistical analysis of drilling data, analytic hierarchy process, and hydrochemical tests, this study analyzed the strata, spatial distribution of aquifers, and the …

Mechanisms Behind Grouting Pressure Jumping In Low-Permeability Limestones And Techniques For Grouting Pressure Control, Fan Zhenli, Cao Lutong, Cui Yong, Zhang Zhiwei, Zhang Fengda

Coal Geology & Exploration

Background The exploitation of the Carboniferous-Permian coalfields in China is gradually transitioning toward coal seams in lower formations. In this context, issues including the confined water hazards in the floor and karst water preservation become increasingly pronounced. During the advanced surface treatment of karst water hazards in coal seam floors, the unclear patterns of matching between grout selection and grouting pressure control lead to empirical parameter selection, thereby yielding poor performance of grouting reinforcement. Methods This study aims to deal with the phenomena of rapid pressure rise with a limited grout volume in the low-permeability argillaceous limestones within the top …

Suitability Evaluation For Deep Geological Storage Of Mine Water In The Ordos Basin, Gulbostan Tursun, Sui Wanghua, Aibibai Mamat, Yang Weifeng, Chen Ge, Gao Liang

Coal Geology & Exploration

Objective Given the issues of large mine water drainage in coal mines in China, as well as the corresponding high treatment cost and low utilization rate, thoroughly investigating efficient, environmentally friendly, economically feasible mine water treatment technologies is the key to the green transformation and the implementation of the sustainable development strategy in the coal industry. Deep geological storage of mine water represents an emerging technology for mine water treatment, enjoying the advantages of low cost and zero emissions. A key step in the application of this technology is to select suitable target reservoirs. Although relevant studies have proposed some …

Advances In Key Technologies For The Management, Restoration, Development, And Utilization Of Coal Mining Subsidence Areas, Meng Zhuanghan, Wang Yutao, Tian Yanzhe

Coal Geology & Exploration

Background Coal mining subsidence areas, formed by the exploitation of coal resources, have emerged as severe challenges to the construction of ecological civilization and the sustainable development of the social economy in China. Their management, restoration, development, and utilization play a significant role in ecological security, food security, and energy transformation. Methods This study aims to address the unresolved and emerging issues in the management of coal mining subsidence areas. Based on the core concepts of management, restoration, development, and utilization, this study developed a dual-level zoning basis system combining theories and reality. Accordingly, coal mining subsidence areas in China …

Design And Efficiency Assessment Of A Passive Treatment System For Acid Mine Drainage, Yan Ruiwen, Zhu Jun, Zhu Junhao, Lin Gang, Zhang Wanqiu, Jia Zenghua, Wang Wenming, Xi Furui

Coal Geology & Exploration

Background Acid mine drainage (AMD) refers to highly acidic, heavy metal-rich effluent generated from mining activities, potentially causing severe environmental contamination. Methods Focusing on the Lujiang alum mine in Anhui Province, this study established a systematic framework for the design and assessment of an integrated passive AMD treatment system using the Phreeqc and AMDTreat software. Based on a comprehensive analysis of the on-site hydrogeochemical characteristics (pH: 2.93‒3.06, Fe: 5.98‒42.52 mg/L, and Al: 18.87‒32.14 mg/L) and physical conditions (flow rate: 50‒96 m³/h, available area: about 50 000 m²), this study proposed a hybrid passive treatment system comprising …

Permeability Evolutionary Patterns Of Fractured Rock Masses In Fault Zones Under Seepage-Stress Coupling, Zhao Dekang, Han Bing, Zeng Yifan, Feng Guorui, Xi Yonghong, Chang Bofeng, Li Zhenghao, Wang Pengwei, Wang Lisan

Coal Geology & Exploration

Background In coal mines, fault structures serve as critical pathways for water inrushes from coal seam floors, posing serious threats to the production safety of mines. Delving into the permeability evolutionary patterns of fractured rock masses in fault zones under seepage-stress coupling holds great significance for the prevention and control of water inrushes along faults from coal seam floors.Methods Against the engineering background of the Gaohe Coal Mine under the Shanxi Lu’an Mining (Group) Co., Ltd. in Shanxi Province, this study analyzed the microscopic physical properties and the pore and fracture structures of a fractured rock mass in a …

Multi-Objective Allocation Optimization Model For Water Resources From A Coal Mine In The Inner Mongolia-Shaanxi Contiguous Area, Miao Hechao, Dong Shuning, Wang Hao, Yang Yuanyuan, Qiao Wei, Wang Xiaodong, Wang Dongqi, Fu Hongyang, Liu Yuting

Coal Geology & Exploration

Objective In China, as coal resource exploitation shifts gradually from eastern to western regions, coal bases in the western region play an increasingly notable foundational role in the basic energy supply in the national economy. However, due to its fragile ecosystems, the safe, efficient, and green coal exploitation of this region has long been challenged by the contradiction between the prevention and control of water hazards and the conservation of water resources. Therefore, advancing intelligent mine water control technology is identified as a crucial method to address the conflicts between coal mining and mine water in the western region. Additionally, …