Numerical Simulation Of Layer-Crossing Propagation Behavior Of
Hydraulic Fractures At Coal-Rock Interface,
2020
Xi’an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi’an 710077, China
Numerical Simulation Of Layer-Crossing Propagation Behavior Of Hydraulic Fractures At Coal-Rock Interface, Li Haozhe, Jiang Zaibing, Shu Jiansheng, Fan Yao, Du Tianlin
Coal Geology & Exploration
Based on the analysis of coal-rock interface, the vertical propagation behavior of hydraulic fractures at coal-roof interface was studied by using finite element method. The influence of some geological and engineering factors on fracture layer-crossing behavior was analyzed. Results have shown that in-situ stress and shear strength of coal-rock interface are the two main factors affecting the fracture propagation at the coal-rock interface. Greater vertical stress difference coefficient and interfacial shear strength make fractures more easier for crossing the interface. Meanwhile, the difference of elastic modulus and tensile strength between coal and rock has less effect on the fracture vertical …
Effect Of White Rot Fungi Pretreatment On Methane Production From Anaerobic
Fermentation Of Coal,
2020
School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China
Effect Of White Rot Fungi Pretreatment On Methane Production From Anaerobic Fermentation Of Coal, Zhang Huaiwen, Huang Song, Yan Xiatong, Zhao Shufeng, Zhang Minglu, Xia Daping
Coal Geology & Exploration
To investigate the effect of white rot fungi pretreatment on methane production from anaerobic fermentation of coal, fermentation experiments of biogas production were conducted using long flame coal. The coal samples pretreated with white rot fungi were the experimental group(EG), and original untreated coal samples were the control group(CG). The COD(chemical oxygen demand) mass concentration, activity of coenzyme F420, and changes of coal morphology were measured using potassium dichromate method, ultraviolet spectrophotometry, and SEM, respectively. The results showed the following: The total gas production and conversion rate in the EG and CG were 2 322.00 mL and 5.10%, 1 330.20 …
Negative Power Rock Strength Criterion Under Conventional Triaxial Compression,
2020
School of Environment and Resource, Southwest University of Science and Technology, Mianyang 621010, China
Negative Power Rock Strength Criterion Under Conventional Triaxial Compression, Li Bin, Wang Daguo
Coal Geology & Exploration
In order to evaluate accurately the rock strength under different confining pressures, a negative power rock strength criterion was proposed according to the upward convex nonlinear relationship between deviator stress and confining pressure during rock failure. The accuracy of the proposed criterion was compared with Mohr-Coulomb criterion and Hoek-Brown criterion. The results showed that the parameters of the negative power criterion are less sensitive to the range of confining pressure, and the negative power criterion could evaluate rock triaxial strength with higher precision. Meanwhile, the applicability of the proposed criterion was verified by using an extensive database of rock triaxial …
The Microscopic Fabric Characteristics Of Biaxial Compression Test Of Typical
Argillaceous Siltstone In Badong Formation,
2020
Xingfa School of Mining Engineering, Wuhan Institute of Technology, Wuhan 430000, China;School of Civil Engineering and Architecture, Wuhan Institute of Technology, Wuhan 430000, China
The Microscopic Fabric Characteristics Of Biaxial Compression Test Of Typical Argillaceous Siltstone In Badong Formation, Xiao Zunqun, Wang Xin, Tang Dongsang, Dong Qiongying, Jiang Yinan, Yang Kai, Cao Tongtong, Deng Zhen
Coal Geology & Exploration
Based on the indoor biaxial compression test of argillaceous siltstone, a numerical model of PFC2D particle flow was established. The model considered the particle shape of the argillaceous siltstone samples. Five typical particle shapes were selected according to the scanning electron microscope, and the circular particles were selected. A stable numerical sample of a given porosity was randomly generated together. The parallel bond contact model was selected between the particles, and the elastic modulus, Poisson’s ratio and peak stress were selected to calibrate the meso-parameters of the saturated and natural argillaceous siltstone samples under different confining pressures, and then the …
Collapses Of Loess At The Front Of The Emei Tableland In The Yuncheng Basin And Their
Major Geological Controlling Factors,
2020
Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China
Collapses Of Loess At The Front Of The Emei Tableland In The Yuncheng Basin And Their Major Geological Controlling Factors, Li Zhenhong, Jiang Boyu, Dong Xiaopeng, Yang Yong, Cui Jiawei, Gong Wangbin
Coal Geology & Exploration
There developed a lot of collapse areas at the front of Emei tableland in Yuncheng Basin, especially around Xinzhuang village. Their evolution process and trend are pivotal issues for evaluating the possibility, time and location of geological hazards. Based on the geological survey in the shallow surface, combining the interpretation of remote sensing data and three-component resonance imaging technique, the surface ground evolution process of the loess collapse area for the past ten years and the present interior structure were summarized. First of all, the front of Emei tableland lies in the transition zone from loess to lacustrine deposits. Therefore, …
Influencing Factors Of Thermal Conductivity Of Cementing
Materials For Geothermal Wells,
2020
China Coal Research Institute, Beijing 100013, China;Xi’an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi’an 710077, China
Influencing Factors Of Thermal Conductivity Of Cementing Materials For Geothermal Wells, Zhang Hao, Xu Shuanhai, Yang Yu, Han Yongliang, Zhang Weidong, Li Yongqiang
Coal Geology & Exploration
The thermal conductivity of cementing materials is one of the factors that affect the heat removal effect of geothermal wells. In order to improve the thermal conductivity of cementing materials for geothermal wells, orthogonal test was used to study the thermal conductivity of cementing materials based on the AHP-CRITIC mixed weighting method and range analysis. The results show that the thermal conductivity of cementing materials can be improved by adding natural flake graphite, iron powder and quartz sand. The content of graphite and the ratio of water to solid are the primary and secondary factors that affect the comprehensive properties …
Progress In Research Of In-Seam Seismic Exploration,
2020
College of Electronic and Information Engineering, Shandong University of Science and
Technology, Qingdao 266590, China
Progress In Research Of In-Seam Seismic Exploration, Guo Yinjing, Ju Yuanyuan, Fan Xiaojing, Zhang Jianhua
Coal Geology & Exploration
after long-term development and improvement, the in-seam seismic(ISS) technology has achieved relatively reliable results in detecting the internal structural development of the coal seam, the thickness variation of the coal seam, and the distribution pattern of the pinch. In order to comprehensively and systematically understand the ISS technology and promote the development of the ISS technology, the status of the ISS technology is reviewed. First, the principle of ISS is briefly described. Then, according to the process of ISS, according to the steps of source excitation, signal acquisition, preprocessing, signal extraction, data processing and analysis, the working principles and methods …
Research And Application Of Mine Distributed Seismic Advance Detection System,
2020
Shanxi Jincheng Anthracite Mining Group Technology Research Institute Co. Ltd., Jincheng 048006, China;State Key Laboratory of Coal and CBM Co-mining, Jincheng 048012, China
Research And Application Of Mine Distributed Seismic Advance Detection System, Dou Wenwu, Wei Jinshan, Jiao Yang, Yang Gaofeng, Ji Zeyu
Coal Geology & Exploration
The mine distributed seismic advance detection system is a set of equipment for detecting the heading geological structure of the mine tunnel. The system is based on the seismic reflection theory. The geologic anomaly is determined by the distributed geophones or the distributed excitation of the source. In order to improve the prediction and prediction accuracy of the structure during coal mining, the distributed observation system and the hole capsule detectors are used for data acquisition to improve the sensitivity of the equipment, the negative apparent velocity principle is used to exclude the interference of the lateral and rear geological …
Paleomagnetic Evidence For Modern-Like Plate Motion Velocities At 3.2 Ga,
2020
Harvard University
Paleomagnetic Evidence For Modern-Like Plate Motion Velocities At 3.2 Ga, Alec R. Brenner, Roger R. Fu, David A.D. Evans, Aleksey V. Smirnov, Raisa Trubko, Ian R. Rose
Michigan Tech Publications, Part 1
The mode and rates of tectonic processes and lithospheric growth during the Archean [4.0 to 2.5 billion years (Ga) ago] are subjects of considerable debate. Paleomagnetism may contribute to the discussion by quantifying past plate velocities. We report a paleomagnetic pole for the ~3180 million year (Ma) old Honeyeater Basalt of the East Pilbara Craton, Western Australia, supported by a positive fold test and micromagnetic imaging. Comparison of the 44°±15° Honeyeater Basalt paleolatitude with previously reported paleolatitudes requires that the average latitudinal drift rate of the East Pilbara was ≥2.5 cm/year during the ~170 Ma preceding 3180 Ma ago, a …
SIT Study Abroad
La Minería Del Litio En Salinas Grandes: Un Análisis De Diferentes Narrativas En Torno A La Extracción De Litio Desde 2010 Hasta El Presente / Lithium Mining In The Salinas Grandes: An Analysis Of Different Narratives Surrounding The Extraction Of Lithium From 2010 Until The Present, Sofia Perrotto
Independent Study Project (ISP) Collection
El litio ha ocupado una posición muy interesante y controvertida dentro del movimiento ambiental desde su descubrimiento en 2010. Entre los muchos usos de este metal precioso está la fabricación de baterías, que es un componente esencial para la transición hacia una "economía verde". Los vehículos eléctricos y las unidades de almacenamiento de energía que funcionan con baterías de litio son dos tecnologías importantes para este movimiento, y como resultado, la demanda de litio está aumentando en el mercado global. En las Salinas Grandes, la cuestión de la extracción de litio involucra a una variedad de actores que tienen diferentes …
Assessing The Energy Management Culture Of Global Leading Mining Companies: Curbing Carbon Emissions In A World Of Growing Climate Change Concerns,
2020
Montana Tech
Assessing The Energy Management Culture Of Global Leading Mining Companies: Curbing Carbon Emissions In A World Of Growing Climate Change Concerns, Irene Ateng
Graduate Theses & Non-Theses
Industries such as the oil, mining and chemical industry have been under a lot of pressure from governments and certain organizations worldwide to reduce their carbon footprint. The United Nations (UN), the International Council on Mining and Metals (ICMM) and other organizations, have mapped out policies and recommendations that can be used to achieve this. Mining companies all over the world have adopted sustainability commitments based on recommendations by the United Nations Intergovernmental Panel on Climate Change and have set targets for managing their energy use and GHG emissions. This research assessed the energy management culture of twenty (20) leading …
The Research Status And Prospect Of Coal-Based Graphite In China,
2020
College of Geoscience and Surveying Engineering, China University of Mining and Technology(Beijing), Beijing 100083, China
The Research Status And Prospect Of Coal-Based Graphite In China, Cao Daiyong, Wang Lu, Liu Zhifei, Ding Zhhengyun, Li Yang, Shu Zhenyu
Coal Geology & Exploration
Coal-based graphite is regarded as a special and non-typical crystalline mineral and belongs to amorphous graphite, which is both the important part of graphite resources and also one of parts of coal measures mineral resources. Coal and coal-based graphite are two different mineral resources which occur at the same place. The graphitization of coal essentially show carbon enrichement and hydrogen and oxygen exclusion in elementary composition and increase of structural ordering degree and the formation of graphite crystals. Coal macerals, magmatic intrusion and geological structure are all critical factors for coal graphitization, which present different characteristics under the influence of …
Investigation On Structural Evolution And Thermal Reaction Of Coal-Based Graphite From Xinhua County, Hunan Province,
2020
College of Geoscience and Surveying Engineering, China University of Mining and Technology(Beijing), Beijing 100083, China
Investigation On Structural Evolution And Thermal Reaction Of Coal-Based Graphite From Xinhua County, Hunan Province, Li Kuo, Liu Qinfu, Song Botao, Zhang Shuai, Wu Yingke
Coal Geology & Exploration
To investigate the structural evolution and thermal reaction of coal-based graphite with different graphitization,the anthracite and coal-based graphite from Xinhua County, Hunan were analyzed by X-ray diffraction (XRD), high resolution transformation electron microscope(HRTEM), and temperature programmed oxidation (TPO). The results show that carbon structure transformed from the amorphous anthracite to three dimensionally ordered graphite as graphitization degree increases. The coal-based graphite samples with different graphitization degree are composed of multi carbon phases, suggesting a heterogeneous nature of coal-based graphite, and ordered carbon phases were common in higher rank samples, however, defects can still be detected in most metamorphosed coal-based graphite. …
Lithium And Gallium Abundance And Enrichment Factors In Typical Late Permian Coal-Accumulating Basin In Guangxi,
2020
Guangxi Bureau of Coal Geological Exploration, China National Administration of Coal Geology, Liuzhou 545005, China
Lithium And Gallium Abundance And Enrichment Factors In Typical Late Permian Coal-Accumulating Basin In Guangxi, Liao Jialong, Zhang Fuqiang, Wei Mengdie, Liang Xingdong
Coal Geology & Exploration
Through systematic sampling and testing of two typical Late Permian coalfields in Fusui and Xian’an, starting with the lithium and gallium abundance of the samples, and combining with the metallogenic geological background of the Late Permian coal-accumulating basin in Guangxi, the factors controlling the enrichment of lithium and gallium in coal are analyzed. The results show that lithium and gallium in coal of both coalfield have certain industrial prospect. Lithium is mainly concentrated in K1 coal seam, carbonaceous mudstone and bauxite section at the bottom of Heshan Formation, while gallium abundance in each lithology at the bottom of Heshan Formation …
Multi-Source Information Evaluation Of Mud And Sand Inrush Disaster During The Mining Of Deep-Buried Coal Seam,
2020
China Coal Research Institute, Beijing 100013, China; Xi’an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi’an 710077, China; Shaanxi Key Lab of Mine Water Hazard Prevention and Control, Xi’an 710077, China
Multi-Source Information Evaluation Of Mud And Sand Inrush Disaster During The Mining Of Deep-Buried Coal Seam, Guo Xiaoming, Guo Kang, Liu Yingfeng
Coal Geology & Exploration
The mud and sand inrush disaster during the mining of deep-buried coal seam is caused by the disintegration of the mudstone in the coal seam roof when meeting water. It is a comprehensive disaster due to concentrated underground mud and sand gush under mine pressure. The occurrence of such disaster is affected by many factors, such as aquifer, mine pressure, and geological structure, etc. This paper took Zhaojin coal mine in Huanglong coalfield as the study area, and discussed the mechanism of the disaster. Then the main controlling factors were identified, including water yield property of Luohe Formation aquifer, distance …
Application Of Far And Near Trace Attributes For Avo Analysis In Deep Water Area In Qiongdongnan Basin,
2020
Zhanjiang Branch Company, China National Offshore Oil Corporation, Zhanjiang 524057, China
Application Of Far And Near Trace Attributes For Avo Analysis In Deep Water Area In Qiongdongnan Basin, Liu Shiyou, Zhang Yingzhao, Li Yangsen, Yan Anju, Zhang Haiyang
Coal Geology & Exploration
For prestack seismic data with low signal-to-noise ratio(SNR), the effect of traditional AVO rendezvous analysis and intercept gradient product attribute(P×G attribute) may not be ideal. In order to extract the information of AVO attribute effectively, this paper starts from the prestack partial superposition body, according to the relative relation of the far and near track part superposition body, the far and near attribute factor similar to the P×G attribute was constructed, in which the near track stack reflects the intercept attribute, and the near-far stack difference reflects the intercept attribute, which is similar to the …
Application Of Small Scale Curvature In Small And Micro-Structure Interpretation Of Coal Field,
2020
Research Institute of Coal Geophysical Exploration, China National Administration of Coal Geology, Zhuozhou 072750, China
Application Of Small Scale Curvature In Small And Micro-Structure Interpretation Of Coal Field, Cheng Yan
Coal Geology & Exploration
The interpretation and delineation of small and micro-structure which acts as one of the main disaster sources in coal mine is an important guarantee for safe and efficient production of coal mines. However, it can't satisfy the geological guarantee for precise mining by only using the traditional seismic exploration methods to solve this problem. Therefore, in this paper, we reconstruct the seismic data by extracting the components above 60 Hz from the 3D seismic data, and then extract minimum negative curvature to interpret and analyze the small and micro-structures in study areas. By comparing the revealed micro-structures and explained results …
Application Of Mine-Hole Joint Microseismic Technology In Monitoring The Damage Depth Of Working Face Floor,
2020
Xi’an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi’an 710077, China
Application Of Mine-Hole Joint Microseismic Technology In Monitoring The Damage Depth Of Working Face Floor, Duan Jianhua, Yan Wenchao, Nan Hanchen, Zhang Qingqing, Fan Xin
Coal Geology & Exploration
Accurate prediction of the mining damage depth of floor is a key problem in the prevention and control of mining floor water hazard especially in the case with confined water. It is very important for developing the strategy of water control. According to the geological characteristics and working face layout of Baode coal mine, Shaanxi Province, a high-precision microseismic monitoring system consisting of well and hole arrays was deployed to detect the floor damage depth in working face 81307 in real time. The velocity model was calibrated and the location accuracy was verified by hammering method. It is proved that …
Forward Response Analysis Of Shield Advanced Detection With Moving Array Electrode,
2020
College of Mechanical Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
Forward Response Analysis Of Shield Advanced Detection With Moving Array Electrode, Zhao Shuanfeng, Bai Yunrui, Huang Tao, Wei Mingle
Coal Geology & Exploration
Aiming at problems of serious electromagnetic interference, difficult application in TBM(Tunnel Boring Machine) tunnel construction and so on, a method of shield advanced detection based on moving array electrodes is adopted. Using Comsol Multiphysics finite element simulation software to establish geoelectric model, forward response analysis is carried out for various geological conditions. The results show that adding the protective electrodes can obviously enlarge the voltage distribution range, which means the detection range increases. In order to improve the detection effect, it is necessary to add protective electrodes. Changes in the size, shape and position of the anomalous body will exhibit …
The Key Technology For Drilling Horizontal Well In Coal Seam Roof In Qianbei Mining Area,
2020
China Coal Research Institute, Beijing 100013, China; Xi’an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi’an 710077, China
The Key Technology For Drilling Horizontal Well In Coal Seam Roof In Qianbei Mining Area, Hu Xinpeng, Zhao Yongzhe, Xu Kanshe, Wang Linjie, Li Peng, Duan Huijun
Coal Geology & Exploration
primary ways to develop the soft coal seam CBM. Aiming at the complex geological conditions and reservoir conditions in Qianbei mining area of Guizhou Province, in order to solve the problems of horizontal well leakage, well trajectory control and solid completion in the horizontal well drilling of coal seam roof, the key technology of horizontal well drilling of coal seam roof in Qianbei mining area, with the accurate control of trajectory as the core, and the technology of preventing leakage, eccentricity and solid completion are combined. Combined with on-site drilling practice, the problems of difficulties in horizontal well drilling were …
