Engineering Commons^™

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

Graduate Theses, Dissertations, and Problem Reports (ETD)

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

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

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

Graduate Theses, Dissertations, and Problem Reports (ETD)

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

Comparison Of Mechanical And Column Flotation Performances On Recovery Of Phosphate Slimes In Presence Of Nano-Microbubbles, Fatemeh Taghavi, Mohammad Noaparast, Ziaeddin Pourkarimi, Fardis Nakhaei

Mining Engineering Faculty Research & Creative Works

Fine particle flotation has been one of the main problems in many mineral processing plants. The bubble-particle collision rate is very low for fine particles, which reduces flotation efficiency. Also, the existence of slimes is, generally, detrimental to the flotation process, affecting the selectivity and the quality of the concentrates. Besides, it causes an increase in reagents consumption. Hence, in most of processing plants, some of these particles are transmitted to the tailing ponds to reduce the effects of these problems and increase the selectivity of the process. Esfordi phosphate plant in Iran loses more than 30% of its capacity …

Depression Of Pyrite In Polymetallic Sulfide Flotation Using Chitosan-Grafted-Polyacrylamide Polymers, Keitumetse Cathrine Monyake

Doctoral Dissertations

“In this work, Chitosan-grafted-Polyacrylamides (Chi-g-PAMs) were studied, for the first time, as selective depressants of pyrite in the flotation of base metal sulfides. Fundamental studies of the adsorption behavior of Chi-g-PAM on model sulfide minerals indicated that Chi-g-PAM was more selective to pyrite’s surfaces as compared to base metal sulfides. Results suggested that the adsorption of Chi-g-PAM at pyrite-water interface was a chemisorption in nature which involved the amine, amide, and hydroxyl groups of Chi-g-PAM. Batch flotation studies of complex sulfide ore of Mississippi Valley Type (MVT) showed that Chi-g-PAM outperformed other pyrite’s depressants at producing less pyrite-diluted concentrates. Statistical …

Static Liquefaction In Tailing Dams, Jose Raul Zela Concha

Graduate Theses, Dissertations, and Problem Reports (ETD)

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

Optimization Of Blast Design For Better Fragmentation & Reduction Of Ground Vibration At Khao Mai Nuan Pyrophyllite Mine, Saraburi Province, Thailand, Arif Khan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Control blasting with better fragmentation is very important to decrease the environmental impacts of blasting and the cost of downstream mining operations such as loading, transportation, crushing, and milling. Proper blasting designs with optimized parameters such as burden, spacing, stemming, sub-drilling, and amount of explosive ensure the required fragmentation with ground vibration within the standards set by different monitoring agencies. This study dealt with the blasting design parameters, fragmentation, and ground vibration at the Khao Mai Nuan Pyrophyllite quarry Saraburi province, Thailand. First, grab samples were collected from the quarry's active benches and tested in a lab for strength, compositions …

Effect Of Salinity Contrast Between Formation Water And Injected Low Salinity Water On Low Salinty Water Flooding In Dolostone Formation, Nuttapol Junput

Chulalongkorn University Theses and Dissertations (Chula ETD)

Low Salinity Waterflooding (LSWF) has gained substantial prominence in current scientific method for oil recovery improvement, owing to its simplicity, cost-effectiveness, and environmental friendliness as an Enhanced Oil Recovery (EOR) technique. Various studies have highlighted the crucial role of injected brine salinity and the concentration of Potential Determining Ions (PDI) in stimulate oil recovery mechanisms. However, the majority of these studies have predominantly concentrated on sandstone reservoirs. In light of the fact that over 50% of hydrocarbon reserves are situated in carbonate reservoirs, this research focuses specifically on dolomite reservoirs to examine the applicability and feasibility of implementing LSWF in …

Simulation Study On Co2 Enhanced Oil Recovery For Offshore Area In Thailand, Pariwat Wongsriraksa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Fossil fuels are widely used all over the world. It generates carbon dioxide (CO2) which is one of the main causes for climate change and global warming. One practical technology to reduce CO2 emission is carbon capture, utilization, and storage (CCUS) which includes the use of CO2 for enhanced oil recovery (CO2EOR) and storage in the geological reservoir. In Thailand, there are some potential geological reservoirs for CO2EOR due to crude properties, depth of the reservoir and oil saturation, especially in the Gulf of Thailand. However, the high temperatures gradient in the Gulf of Thailand can lead to higher minimum …

Physical Property Measurement Of Surfactant Coupled With Nanoparticles For Enhanced Oil Recovery, Phoo Pwint Nandar

Chulalongkorn University Theses and Dissertations (Chula ETD)

The residual oil remained in the reservoir after the primary recovery and water flooding can either be produced by increasing the mobility of the oil or by altering the reservoir rock wetting behavior and diminishing the oil water interfacial tension. The surfactant flooding is one of the chemical enhanced oil recovery methods. At the optimal concentration, the surfactant flooding can provide the low interfacial tension favoring to the enhanced oil recovery. In contrast, the loss of the surfactant at the solid-liquid interface due to an adsorption lessens the amount of the surfactant required for oil displacement during the flooding. Therefore, …

Effect Of Salinity Contrast Between Formation Water And Injected Low Salinity Water On Low Salinity Waterflooding In Shaly-Sandstone Formation, Sarun Phuenghansaporn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Low salinity waterflooding is an improving oil recovery technique that is highly mentioned nowadays as it is cost-efficient and environmentally friendly. The technique involves injecting water with lower salinity compared to formation salinity to shift the surface equilibrium toward the liberation of oil from the rock surface. Nevertheless, successful of this technique depends on many parameters especially the presence of clays. Several types of clays can be found in oil reservoirs, and they may react to different cations in inject low salinity in different ways, resulting in different magnitudes of oil recovery. Moreover, the contrast of salinity between formation water …

Pore Pressure Prediction Using Combination Drilling Efficiency And Hydro-Mechanical Specific Energy Methods, Munawir Arge Pratama Otolomo

Chulalongkorn University Theses and Dissertations (Chula ETD)

Several methods of pore pressure prediction using drilling parameters were introduced and improved to meet the challenges of accurate prediction at a relatively low cost. Knowledge of pore pressure is essential for safe well planning, cost-effective drilling, and operational decision-making. Conventional methods in pore pressure prediction using drilling parameters have limitations on its application of making the normal compaction trendline that is only applicable in clean shale intervals. In this work, the concept of drilling efficiency (DE) and hydro-mechanical specific energy (HMSE) for predicting formation pore pressure is proposed. This method, termed DE-HMSE, is based on the theory that the …

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

Graduate Theses, Dissertations, and Problem Reports (ETD)

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

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

Graduate Theses, Dissertations, and Problem Reports (ETD)

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

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

Graduate Theses, Dissertations, and Problem Reports (ETD)

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

Saxs-Based Nano-Scale Pore Structure Characteristics Of Coals With Different Metamorphic Degrees, Zhang Yu, Li Yong, Wang Yanbin, Wang Zhuangsen, Zhao Shihu, Han Wenlong

Coal Geology & Exploration

In order to reveal the characteristics of nano-scale pores in coals with different metamorphic degrees, the small-angle X-ray scattering method (SAXS) is used to obtain the porosity, pore size distribution, specific surface area and fractal dimension of 15 samples whose vitrinite reflectance R_max is 0.31%-6.24%, and the low temperature CO₂ and N₂ adsorption DFT model results are used to verify the pore size distribution. The results show: during coalification process, when R_max is < 0.5%, the porosity and the specific surface area of coal increase with the increase of metamorphic degree, the micropores(< 2 nm) content increases seldomly, the mesoporous(2-50 nm) and microporous(50-100 nm) content increase greatly, and the surface of coal is gradually smooth. When R_max=0.5%-1.4%, the porosity and the specific surface area decrease, and each type of pore content is reduced, and the surface of …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Geochemical Characteristics Of Marine-Continental Transitional Facies Shale And Shale Gas In Linxing Area, Chen Xin, Wu Peng, Gao Jixian, Hu Weiqiang, Ding Wangui, Li Yangbing, Liu Xueqing, Ma Litao, Liu Cheng, Kong Wei, Cao Di, Chen Jianqi, Li Yong

Coal Geology & Exploration

In order to reveal the geochemical characteristics of shale and shale gas on the east edge of Ordos Basin, thin section identification, full rock and clay content, scanning electron microscope, organic carbon, rock pyrolysis, kerogen macerals, and kerogen carbon isotopes were tested, and the gas component and carbon isotopes composition of shale were analyzed. The results show that the mineral component of the transitional facies shale in Linxing area is mainly quartz and clay minerals, containing a small amount of calcite, plagioclase, potassium feldspar, dolomite and pyrite. Affected by the mineral genesis and deposition environment, different mineral components and organic …

Geological Characteristics And Reservoir-Forming Potential Of Shale Gas Of Transitional Facies In Linxing Area, Eastern Margin Of Ordos Basin, Wu Peng, Cao Di, Zhu Guanghui, Liu Xueqing, Li Yong, Li Yangbing, Hu Weiqiang, Liu Zaizhen, Kong Wei, Fei Jingliang

Coal Geology & Exploration

Shale gas of transitional facies is the important replacing area for increase of shale gas reserves and production. On the basis of the experiment and research data of shale of transitional facies of Linxing area in the eastern margin of Ordos Basin, by selecting the strata series of Shanxi Formation, Taiyuan Formation and Benxi Formation as the research object, from the sedimentary environments, shale distribution, organic geochemical characteristics, mineralogy, physical characteristics and gas-bearing characteristics, etc., the geology characteristics of the shale gas transitional facies in the study area were summarized and dissected systematically to analyze its enrichment and reservoir-forming potential. …

Qualitative-Quantitative Multi Scale Characteristics Of Shale Pore Structure From Upper Paleozoic Coal-Measures In Linxing Area, Liu Cheng, Ding Wangui, Zhang Jian, Chen Xin, Wu Peng, Liu Xueqing, Li Yangbing, Ma Litao, Hu Weiqiang, Kong Wei, Li Yong

Coal Geology & Exploration

In order to reveal the micro-pore structure characteristics of marine-continental transitional shale and its main controlling factors in the eastern margin of Ordos Basin, and to enrich the understanding of pore development characteristics and pore structure of marine-continental transitional coal-bearing shale in the block, scanning electron microscope, high-pressure mercury injection and liquid nitrogen adsorption analysis were used to characterize the micro-pore structure characteristics of shale in Linxing area. Furthermore, porosity, total content of organic carbon, mineral content, clay relative content and organic matter maturity were tested to study the main controlling factors of development of shale pore structure. The results …

Characteristics Of Shallow Coal Measure Gas Reservoir And Key Technologies Of Exploration And Development In Yaojie Mining Area, Du Xinfeng, Yuan Chongliang, Wang Zhengxi, Wang Junde, Li Shibing, Liu Jingdan, He Xiuqing, Zhang Tianguo, Shan Yuanwei, Fang Jiawei

Coal Geology & Exploration

The exploration and development of coal measures gas can not only effectively improve the single well production of coalbed methane in coal mining areas, reduce the waste of resources, but also alleviate the energy crisis in China, reduce coal mine gas accidents, protect the atmospheric environment, and contribute to the realization of carbon peak and carbon neutralization. Based on the shallow coal measure gas development demonstration project in the third mining area of Haishiwan mine field, the characteristics of coal measure gas reservoirs in Yaojie mining area are analyzed, and the key technologies for coal-measure gas exploration and development are …

Cbm Well Drainage Data-Based Dynamic Inversion Study Of Reservoir Gas Content, Ma Dongmin, Ji Yusong, Chen Yue, Zheng Chao, Teng Jinxiang, Ma Zhuoyuan, Xiao Jialong

Coal Geology & Exploration

The gas content of coal reservoir is the core parameter of coalbed methane production. There is an error between the measured gas content and the real gas content of coal reservoir. In this paper, based on the gas production of Haishiwan coalbed methane wells in different periods and the decrease of the "constant volume" of the gas content of coal reservoirs, the real-time gas content of coal reservoirs is inverted, and the change rule of the real-time gas content in the process of coalbed methane well drainage is explored. The results show that: (1) The gas content of coal reservoir …

Physical Modeling Of Seismic Response For The Coal Seams Of Yan'an Formation In Loess Tableland Of North China, Xing Tingdong, Xue Shigui, Li Xiaowei, Suo Chonghui, Wang Huiming, Jiao Yanyan

Coal Geology & Exploration

A seismic physical simulation is carried out for the complex seismic response of the coal seam of Yan'an Formation in the loess tableland. First, the physical model materials for the dry layer near the surface of the loess tableland and the coal seam are developed. After several tests, a mixture of silicone rubber with silicon aerogel powder is selected to simulate the surface of the loess tableland, and the mixture with ultra-fine carbon powder added to silicone rubber is used to simulate the low-speed and low-density coal seam. Through the methods of molds control layer, layer by layer pouring, three-dimensional …

3d Seismic Physical Modeling Acquisition Technology And Its Application, Liu Qiang, Shi Xianxin, Hu Jiwu, Dong Ruijing, Lian Chenguang

Coal Geology & Exploration

Seismic physical modeling acts as a bridge between the research on seismic theoretical methods and actual seismic exploration, which is an important means of studying the propagation law of the elastic wave field and verifying the processing and interpretation methods. It plays an important role of theoretical supporting in the field of oil & gas seismic exploration. There is a great difference between coalfield and oil & gas in seismic exploration attributes, and no professional automatic seismic physical modeling system has been built in the field of coal field seismic exploration. Therefore, a large professional 3D seismic physical modeling system …

Design And Construction Of A Seismic Physical Model Of Room-Pillar Goafs In Shallow Coal Seams, Wang Pan, Zhu Shujie, Jia Qian, Jian Benqi, Lian Miaomiao, Dong Ruijing

Coal Geology & Exploration

In view of the problem of low detection accuracy of room-pillar goafs in shallow coal seams in northern Shaanxi, the seismic physical model is designed for physical simulation according to the principle of similarity ratio of geometry size and wave impedance. Through a large number of ratio tests of similar materials, the ratio of epoxy resin and silicone rubber is determined as 1 : 1.2 for similar materials of low velocity loess layer, 1 : 0.2 : 0.6 for epoxy resin, silicone rubber and talc for mudstone, 1 : 0.4 for epoxy resin and silicone rubber for coal seams, 1 …

Discussion On The Recommended Models For Resource Reuse Of Closed Coal Mines In Main Mining Areas Of Hebei Province, Yin Quanzeng, Chen Zhongshan, Feng Qiyan, Geng Lijuan, Lian Lixun, Li Fang, Liu Ning

Coal Geology & Exploration

The evaluation and the utilization of the resources of the closed coal mines have dual benefits of resources and environment, and can provide a transformation and development path for coal mining enterprises. Based on the investigation of the resources of the closed coal mines in the main mining areas of Hebei Province, through the summary of the typical cases of the resources reuse of the closed coal mines at home and abroad and in Hebei Province, this paper sums up 7 types and 19 kinds of recommended modes of the resources reuse of the closed coal mines in Hebei Province, …

Plastic Deformation-Based Constitutive Relation Of Coal Damage And Permeability Model, Wu Xuehai, Li Bobo, Wang Xin, Gao Zheng, Li Jianhua, Xu Jiang

Coal Geology & Exploration

Coal and gas outburst induced by mining disturbance is one of the main gas dynamic disasters in coal mine production. In order to systematically explore the evolution characteristics of coal damage and the law of gas seepage under mining disturbance, the whole stress strain–seepage experiment under different gas pressures was carried out. The generalized Hooke's law was modified by considering the effects of gas adsorption and thermal expansion, the plastic deformation-based constitutive relation of coal damage was established, and the piecewise permeability model considering the damage was further constructed. The results shown that the coal permeability can be divided into …

Prevention And Control Technology Of Goaf Water Hazard In Unauthorized Mining Areas Of Extremely Soft And Medium-Thick Coal Seams, Li Zhi, Zheng Shitian, Shi Zhiyuan, Wang Yuhang

Coal Geology & Exploration

Unauthorized mining in coal pit is common in China's coal industry. As the scope of unauthorized mining and the amount of accumulated water are hard to determine, the goaf water seriously threatens the safety of mining in adjacent large coal mines. In order to explore the unauthorized boundary of coalpits quickly and accurately and prevent the threat of goaf water, the long distance drilling technology of ground bedding borehole in medium and thick coal seam is proposed based on the controllable trajectory and accurate positioning of ground directional drilling, which mainly includes precise drilling in extremely soft and medium-thick coal …

Prediction Model Of Water Inrush From Coal Floor Based On Ga-Bp Neural Network Optimized By Ssa And Its Application, Yin Huiyong, Zhou Xinlong, Lang Ning, Zhang Lifeng, Wang Mingli, Wu Tao, Li Xin

Coal Geology & Exploration

With the increase of coal mining depth, coal production process is faced with complex water inrush mechanism and variable water inrush main control factors, and the uncertainties among the factors make the prediction of floor water inrush more difficult. In order to accurately predict the risk of floor water inrush, aiming at the small sample and non-linear problem of floor water inrush, firstly, genetic Algorithm is used to optimize the initial weights and thresholds of network random assignment, and then Sparrow Search Algorithm with strong search ability and good stability is selected to optimize the weights and thresholds for the …

Interfacial Shear Behavior Of Gabion Reinforced Coal Gangue And Stability Of Embankment Slope, Yang Guolin, Chen Zi'ang, Duan Junyi, Zhang Yu, Zhang Zhen

Coal Geology & Exploration

In order to make full use of coal gangue generated in coal mining and support the carbon neutral policy, the road section K128+573–K128+740 of Anshao Highway (Anhua-shaoyang, Hunan Province)was filled by coal gangue, and the embankment slope was enhanced by gabion net. The basic characteristics of coal gangue were obtained by its chemical composition and gradation, and shear characteristics of gabion reinforced coal gangue were tested by large-scale direct shearing instrument. Finally, the influence of reinforcement and its method on the stability of reinforced coal gangue embankment was found out by finite difference method. The experimental results show that after …

Application Of Unmanned Aerial Vehicle In Surface Soil Characterization And Geological Disaster Monitoring In Mining Areas, Long Linli, Liu Ying, Zhang Xuyang, Su Yongdong, Chen Xiaoyang

Coal Geology & Exploration

With the emergence and development of UAVs and the improvement of the miniaturization and intelligence of various sensor, UAVs equipped with sensors have become an efficient tool for obtaining spatial data. Because UAVs are low cost, short revisit period, fast and efficient, light and flexible, simple operation, and high temporal and spatial accuracy of image acquisition, it is widely used in mining land damage monitoring. Using "UAV, Inversion, Soil Monitoring, Surface Collapse, Ground Fissure" as keywords, this paper summarizes the academic papers of the search system in the web of science, CNKI, and Google Scholar from January 2010 to May …