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Articles 1591 - 1620 of 1943

Full-Text Articles in Mining Engineering

Development Situation And Prospect Of Luffing Mechanism Of Drilling Rig In Underground Coal Mine, Yao Yafeng, Yao Ningping, Peng Tao Apr 2020

Development Situation And Prospect Of Luffing Mechanism Of Drilling Rig In Underground Coal Mine, Yao Yafeng, Yao Ningping, Peng Tao

Coal Geology & Exploration

The luffing mechanism of drilling rig is used to adjust the opening parameters of the borehole, that is, azimuth angle, inclination angle, and height. According to the structural differences of different types of drilling rig and the construction characteristics of borehole in underground coal mine, this paper summarizes the adjustment requirements to opening parameters and proposes the research goal, which can rapidly and accurately adjust the parameters of the borehole and safeguard the stability of drilling construction. It is concluded that the luffing mechanism of drilling rig in underground coal mine has overall characteristics of small size, large adjustment range …


Development Of Small Diameter Hydraulic Agitator With Cable For Directional Drilling In Underground Coal Mine, Wang Li, Xu Baolong, Wang Yi, Huang Hanjing, Jia Mingqun, Ma Bin Apr 2020

Development Of Small Diameter Hydraulic Agitator With Cable For Directional Drilling In Underground Coal Mine, Wang Li, Xu Baolong, Wang Yi, Huang Hanjing, Jia Mingqun, Ma Bin

Coal Geology & Exploration

Aiming at the problems of large drilling pressure, low drilling efficiency and limited hole depth caused by the backing effect of drill string during deep hole directional drilling in underground coal mine, the technical idea of using hydraulic agitator was proposed. The ø89 mm small diameter hydriculic agitator was designed based on valve principle, the exciting force, excitation frequency were identified, and the cabled sub was developed. The performance parameters of hydraulic agitator with disc spring and cylindrical spring were tested. The results show that when the flow rate of 300 L/min the disc spring hydraulic agitator has the maximum …


Discussion And Application Of Geological Evaluation Index Of Scarce Coal Injected Into Blast Furnace, Qiao Junwei, Li Zhengyue, Chen Meiying, Lyu Jun’E Apr 2020

Discussion And Application Of Geological Evaluation Index Of Scarce Coal Injected Into Blast Furnace, Qiao Junwei, Li Zhengyue, Chen Meiying, Lyu Jun’E

Coal Geology & Exploration

Coal injected into blast furnace can reduce the use of coke, is an important technical measure to reduce the production cost and improve the economic benefit of modern blast furnace. From the influential factors of quality of coal injected into blast furnace and on the basis of evaluation of quality of high-quality coal and scarce coal, the geological evaluation indexes and the grading parameters of scarce coal injected into blast furnace were discussed. The evaluation indexes of coal quality for blast furnace are divided into process index and economic index. Process index is the key index to determine whether coal …


Solid-Liquid Migration Of Molybdenum In Stone Coal And Coal Ash In Southern Shaanxi, Zhang Weiguo, Li Huantong, Wang Feng, Yang Fu, Teng Jinxiang Apr 2020

Solid-Liquid Migration Of Molybdenum In Stone Coal And Coal Ash In Southern Shaanxi, Zhang Weiguo, Li Huantong, Wang Feng, Yang Fu, Teng Jinxiang

Coal Geology & Exploration

Molybdenum is a typical environmental sensitive element, and also a potential rare metal element. In order to find out the content characteristics of molybdenum in raw stone coal and coal ash and the migration rule between solid and liquid, stone coal and coal ash in southern Shaanxi Province were selected as the research object, and the molybdenum content in samples was analyzed by ICP-MS. To analyse the leaching rate of molybdenum from stone coal and coal ash in four different liquids, pure water, scid, alkaline and mine drainage were selected to simulate soaking experiment. The results show that the content …


Petrographic, Quality Characteristics And Clean & Efficient Use Of Jurassic Coal In Ningdong Coalfield, Du Fangpeng, Luo Zheng, Qiao Junwei, Zhao Xiaochen, Tan Furong, Li Congcong, Fan Qi Apr 2020

Petrographic, Quality Characteristics And Clean & Efficient Use Of Jurassic Coal In Ningdong Coalfield, Du Fangpeng, Luo Zheng, Qiao Junwei, Zhao Xiaochen, Tan Furong, Li Congcong, Fan Qi

Coal Geology & Exploration

Jurassic coal resources in Ningdong coalfield are huge, also play important role in coal resource development and utilization in Ningxia. For the purpose of clean and efficient use of Jurassic coal in Ningdong coalfield, coal quality and petrographic characteristics were analyzed based on coalfield exploration data. The results show that Jurassic coal in Ningdong coalfield is characterized by very low to low ash, very low to low sulfur content, low phosphorus, low arsenic, low fluorine and high heating value, these characters indicate that Jurassic coal is clean power coal. Besides that, it has medium to high volatile, higher H/C, lower …


Characteristics Of Tectonic Evolution Of Carboniferous-Permian Coal Measures In The North-Central Qinshui Basin, Lin Zhongyue, Liu Kang, Wei Yingchun Apr 2020

Characteristics Of Tectonic Evolution Of Carboniferous-Permian Coal Measures In The North-Central Qinshui Basin, Lin Zhongyue, Liu Kang, Wei Yingchun

Coal Geology & Exploration

By restoring the paleo-tectonic and sedimentary environment of coal accumulation period, combining with the tectonic stress field and subsidence history, the formation process of Late Paleozoic coal measures in the North-central Qinshui basin and the influence of multi-stage tectonic movement on the occurrence of coal measures minerals were comprehensively analyzed. It is considered that during the C-P coal-accumulating period, the NE-trending sedimentary depression controlled the present tectonic framework of the basin. During Indosinian period, the basin underwent rapid subsidence and formed coal measures gas under the action of deep metamorphism. During Yanshanian period, the basin was destroyed by compression, the …


Numerical Simulation Of Layer-Crossing Propagation Behavior Of Hydraulic Fractures At Coal-Rock Interface, Li Haozhe, Jiang Zaibing, Shu Jiansheng, Fan Yao, Du Tianlin Apr 2020

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, Zhang Huaiwen, Huang Song, Yan Xiatong, Zhao Shufeng, Zhang Minglu, Xia Daping Apr 2020

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, Li Bin, Wang Daguo Apr 2020

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, Xiao Zunqun, Wang Xin, Tang Dongsang, Dong Qiongying, Jiang Yinan, Yang Kai, Cao Tongtong, Deng Zhen Apr 2020

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, Li Zhenhong, Jiang Boyu, Dong Xiaopeng, Yang Yong, Cui Jiawei, Gong Wangbin Apr 2020

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, Zhang Hao, Xu Shuanhai, Yang Yu, Han Yongliang, Zhang Weidong, Li Yongqiang Apr 2020

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, Guo Yinjing, Ju Yuanyuan, Fan Xiaojing, Zhang Jianhua Apr 2020

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, Dou Wenwu, Wei Jinshan, Jiao Yang, Yang Gaofeng, Ji Zeyu Apr 2020

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 …


The Research Status And Prospect Of Coal-Based Graphite In China, Cao Daiyong, Wang Lu, Liu Zhifei, Ding Zhhengyun, Li Yang, Shu Zhenyu Feb 2020

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, Li Kuo, Liu Qinfu, Song Botao, Zhang Shuai, Wu Yingke Feb 2020

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, Liao Jialong, Zhang Fuqiang, Wei Mengdie, Liang Xingdong Feb 2020

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, Guo Xiaoming, Guo Kang, Liu Yingfeng Feb 2020

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, Liu Shiyou, Zhang Yingzhao, Li Yangsen, Yan Anju, Zhang Haiyang Feb 2020

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, Cheng Yan Feb 2020

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, Duan Jianhua, Yan Wenchao, Nan Hanchen, Zhang Qingqing, Fan Xin Feb 2020

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, Zhao Shuanfeng, Bai Yunrui, Huang Tao, Wei Mingle Feb 2020

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, Hu Xinpeng, Zhao Yongzhe, Xu Kanshe, Wang Linjie, Li Peng, Duan Huijun Feb 2020

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 …


Numerical Simulation Of Rupture Process Of Shale Under Action Of Fluid-Solid Coupling, Lou Yili, Wu Zhonghu, Wang Anli, Zuo Yujun, Liu Hao, Sun Wenjibin Feb 2020

Numerical Simulation Of Rupture Process Of Shale Under Action Of Fluid-Solid Coupling, Lou Yili, Wu Zhonghu, Wang Anli, Zuo Yujun, Liu Hao, Sun Wenjibin

Coal Geology & Exploration

In order to investigate the rupture process and acoustic emission characteristics of shale under fluid-solid coupling, the numerical simulation of fluid-solid coupling of the Niutitang Formation shale in different bedding angle in the northern part of the Qianbei area was carried out by RFPA2D-Flow numerical software. Studies have shown that due to the influence of the bedding structure, the compressive strength and elastic modulus of shale show obvious anisotropy. The rupture process of shale can be divided into three stages: elasticity, yielding and destruction. With the change of the bedding angle, the shale finally showed three failure modes, namely oblique …


Thermal Short-Circuiting And Heat Transfer Performance Of Coaxial Borehole Heat Exchanger, Li Yongqiang, Xu Shuanhai, Zhang Weidong, Sun Yuliang, Han Yongliang, Zhang Hao, Huang Jianfeng Feb 2020

Thermal Short-Circuiting And Heat Transfer Performance Of Coaxial Borehole Heat Exchanger, Li Yongqiang, Xu Shuanhai, Zhang Weidong, Sun Yuliang, Han Yongliang, Zhang Hao, Huang Jianfeng

Coal Geology & Exploration

The coaxial heat exchanger is a commonly used device for deep ground source heat pump systems. Based on the fluid flow heat transfer equation, the coupled heat transfer model of the coaxial heat exchanger and the surrounding rock mass is established. Taking the first heating period as an example, the influence of the inner tube thermal conductivity and circulating water flow on the heat transfer performance was analyzed, and the heat exchanger efficiency was introduced to evaluate the thermal short-circuiting phenomenon. The following conclusions were obtained: The phenomenon of thermal short circuit becomes obvious with the increase of the thermal …


Geosteering Technology And Cbm Horizontal Well Drilling Without Pilot Hole, Liu Mingjun, Li Bing, Huang Wei Feb 2020

Geosteering Technology And Cbm Horizontal Well Drilling Without Pilot Hole, Liu Mingjun, Li Bing, Huang Wei

Coal Geology & Exploration

Aiming at the difficulties of hole-forming of the horizontal interval in a soft coal seam, low drilling ratio of coal seam and need of pilot hole during deflecting drilling, the key technologies such as drilling parameter optimization, anti-collapse drilling were put forward in the paper. Geosteering technology with multi-markers was used to realize timely layer identification, to search suitable targeting angle, to be adaptive to the stratum dip so as to realize one time direct landing at the target. Geosteering and geometric steering were combined to control finely the wellbore trajectory of the horizontal interval, to make the wellbore trajectory …


Raman Spectrum Characteristic And Structural Evolution Of High Rank Coalscryptocrystalline Graphite, Li Huantong, Wang Nan, Zhu Zhirong, Fan Jingjing, Zhang Weiguo Feb 2020

Raman Spectrum Characteristic And Structural Evolution Of High Rank Coalscryptocrystalline Graphite, Li Huantong, Wang Nan, Zhu Zhirong, Fan Jingjing, Zhang Weiguo

Coal Geology & Exploration

Raman spectroscopy can reflect the order degree and structural defects of carbon materials, and can be used to characterize the structural changes during the evolution of high rank coal-cryptocrystalline graphite, and analyze the relationship between Raman parameters of coal with different deformation and metamorphic degrees and the spacing of surface network(d002). The results showed that: (1) there was stepped variation between the G peak position and d002, but the graphite and high rank coal could be distinguished well. The S2 peak, the full width at half maximum of D1 and G had a good linear relationship with d002; (2) the …


Characteristics And Sedimental Control Of Mine Water Outflow In Hujirt Mining Area, Liang Xiangyang, Yang Jian, Cao Zhiguo Feb 2020

Characteristics And Sedimental Control Of Mine Water Outflow In Hujirt Mining Area, Liang Xiangyang, Yang Jian, Cao Zhiguo

Coal Geology & Exploration

Hujirt mining area in Ordos basin is a deep-buried Jurassic coalfield with high water pressure, large water volume and uneven water abundance. Each mine is facing serious pressure of mine water hazard prevention and control. In order to clarify the water outflow conditions and main controlling factors of the coal seam roof of the mine in this area, the research on geological deposit and water-producing horizon of roof boreholes, water-inrush from boreholes and water-inrush from working face was carried out. The results showed that within the water conducting fractured zone of Hujirt mining area, there are mainly meandering river sedimentary …


Development And Application Of Macroscopic And Mesoscopic Analytical Testing Instrument For Reinforcement-Soil Interface Characteristics, Yi Fu, Du Changbo, Wang Zhengyun, Yu Ben Feb 2020

Development And Application Of Macroscopic And Mesoscopic Analytical Testing Instrument For Reinforcement-Soil Interface Characteristics, Yi Fu, Du Changbo, Wang Zhengyun, Yu Ben

Coal Geology & Exploration

To analyze the interaction characteristics of soil-reinforcement interface more comprehensively, an experimental instrument for macro-and micro-analysis of interface characteristics of visible reinforced soils was developed and can be used for direct shear and pull-out tests with different geosynthetics and fillers. The instrument improves the size of test box, facilitates the comparative analysis of the two tests, and has an image recording system which enables the microscopic analysis of test process. The direct shear and pull-out tests of geosynthe­tics(geogrid and geotextile) reinforced tailings sand were carried out with the newly developed apparatus. The results show that the interface parameters(pseudo-cohesion and pseudo …


Table Of Contents, The Editors Feb 2020

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.