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- Keyword
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- Numerical simulation (87)
- Coalbed methane (47)
- Coal mine (39)
- Ordos Basin (31)
- Gas drainage (28)
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- Deep learning (27)
- Permeability (27)
- Pore structure (27)
- Coalbed methane (CBM) (25)
- Deep coalbed methane (24)
- Hydraulic fracturing (23)
- Tar-rich coal (23)
- Directional drilling (21)
- Underground coal mine (20)
- Coal (17)
- Deep coalbed methane (CBM) (17)
- Qinshui Basin (15)
- Horizontal well (14)
- Open-pit coal mine (14)
- Rock burst (14)
- Shale gas (13)
- Underground coal gasification (UCG) (13)
- Fracture (12)
- Machine learning (12)
- Mine water (12)
- Prospect (12)
- Fractal dimension (11)
- Helium (11)
- Intelligent mining (11)
- Microstructure (11)
- Publication Year
Articles 1741 - 1770 of 1799
Full-Text Articles in Engineering
Trajectory Design Of Oblique Section In Nearly Horizontal Directional Hole In Inclined Formation In Underground Coal Mine, Zhang Yingjie, Zhao Yongzhe, Yang Zhong, Mo Haitao
Trajectory Design Of Oblique Section In Nearly Horizontal Directional Hole In Inclined Formation In Underground Coal Mine, Zhang Yingjie, Zhao Yongzhe, Yang Zhong, Mo Haitao
Coal Geology & Exploration
Trajectory design of the near-horizontal directional drilling technology in underground coal mine is one of key aspects to successfully implement the technology. The trajectory of hole in a nearly horizontal formation is designed generally by two-dimensional method, and this method usually leads to the problem that the deflecting section of the hole travels out of the inclined target formation.Therefor, the calculation methods of the drilled formation true thickness were studied in the paper, the method using the unit normal vector of formation was proposed, and computation table in Excel was developed to guide trajectory design of near-horizontal directional drilling. The …
Experimental Of Water Unlocking Stimulation Mechanism On Surfactant Fracturing Fluid, Song Jinxing, Yu Shiyao, Su Xianbo, Wang Qian
Experimental Of Water Unlocking Stimulation Mechanism On Surfactant Fracturing Fluid, Song Jinxing, Yu Shiyao, Su Xianbo, Wang Qian
Coal Geology & Exploration
This paper presents an experimental study of water unlocking stimulation mechanism on surfactant fracturing fluid based on the measurements of surface tension, contact angle, gas-phase permeabilities and desorption of nitrogen on synthetic coal samples. The coking coal in Liulin zone of Hedong coal field was used as testing object in this study. Active water and surfactant fracturing fluids were used as testing liquids in this study. Results show that the surfactant fracturing fluid(1.5%KCl+0.05%AN) reduces the surface tension of active water fracturing fluid(1.5%KCl) and increases the wettabil-ity of active water fracturing fluid to coal reservoir; the surfactant fracturing fluid reduces the …
The Characteristics Of Organic Matter In Coal-Measure Source Rocks And Coal-Measure Gas Resource Potential In Eastern Henan Province, Yang Yanqing, Zhang Xiaodong, Xu Yakun, Zhang Peng, Wang Kun, Zhu Chunhui
The Characteristics Of Organic Matter In Coal-Measure Source Rocks And Coal-Measure Gas Resource Potential In Eastern Henan Province, Yang Yanqing, Zhang Xiaodong, Xu Yakun, Zhang Peng, Wang Kun, Zhu Chunhui
Coal Geology & Exploration
In order to evaluate the hydrocarbon generation potential of coal-measure source rocks in eastern Henan Province, based on the measurement results of organic carbon content, vitrinite reflectance and the identification of maceral and type of kerogen in source rocks, the organic geochemical characteristics and the resource potential of coal-measure gas in different blocks of eastern Henan Province were comprehensively analyzed, and favorable blocks for coal-measure gas exploration were designated. The results show that the organic carbon mass fraction of coal-measure source rocks presents low as a whole(less than 1.5%). Kerogen in coal-measures source rocks is mainly of type Ⅲ and …
Analysis Of Water Abundance Characteristics Of Sandstone Aquifer In Luohe Formation On The Basis Of Arcgis, Hou Enke, Long Tianwen, Liu Qingli, Wang Fei, Fan Zhigang
Analysis Of Water Abundance Characteristics Of Sandstone Aquifer In Luohe Formation On The Basis Of Arcgis, Hou Enke, Long Tianwen, Liu Qingli, Wang Fei, Fan Zhigang
Coal Geology & Exploration
Aquifer water abundance evaluation is the prerequisite for coalmine water inflow prediction and water disaster prevention. Luohe aquifer is the roof of No.4 coal seam on panel 41 in Wenjiapo mine. Six main controlling factors of Luohe aquifer chosen to assess coal water abundance are aquifer thickness, porosity, moisture content, washing liquid consumption and apparent resistivity of upper and lower Luohe Formation. Analytic hierarchy process(AHP) has been used to determine the weight of each control factor. Based on ArcGIS numerical visualization platform, the vector maps of factors are normalized and superimposed, and then water abundance evaluation model of aquifer based …
Fuzzy Random Optimization Of Generalized Kelvin Constitutive Model For Creep Of Artificial Freezing Clay, Yao Yafeng, Cheng Hua, Rong Chuanxin, Zhang Nan, Lin Jian
Fuzzy Random Optimization Of Generalized Kelvin Constitutive Model For Creep Of Artificial Freezing Clay, Yao Yafeng, Cheng Hua, Rong Chuanxin, Zhang Nan, Lin Jian
Coal Geology & Exploration
The constitutive model of freezing creep is one of the important reference data for shaft building using freezing method. Uniaxial creep tests under different stress levels were conducted for the artificial freezing clay at -5℃, -10℃, -15℃ and -20℃. So the changing rules of creep curves were obtained under the condition of different temperatures and different stress levels. On this basis, traditional Guess-Newton algorithm has been improved by fuzzy random iterative search and the of the fuzzy random Guess-Newton algorithm steps were obtained, then we use the improved algorithm to optimize the parameters of the generalized Kelvin constructive model, obtained …
Clgis Logging Data Format Conversion, Lin Jiamin, Zhang Gong
Clgis Logging Data Format Conversion, Lin Jiamin, Zhang Gong
Coal Geology & Exploration
In order to solve the problem of DAT log data format conversion, well logging data of CLGIS(Coalfield Logging Geology Interpretation System) is analyzed in detail. On the basis of analysis of the data storage format, format conversion program is written. The program can accurately convert the DAT format data to LAS format data promptly. The LAS format data can be loaded into the commonly used well logging software in oil field easily. With the help of powerful software, the drawing efficiency and quality of coalfield well logging is greatly improved.
Mechanical Characteristics And Test Of Rotary Drilling Of Pdc Anchor Bit, Zhang Youzhen, Zhang Ning, Zhang Xianzhen
Mechanical Characteristics And Test Of Rotary Drilling Of Pdc Anchor Bit, Zhang Youzhen, Zhang Ning, Zhang Xianzhen
Coal Geology & Exploration
For the construction requirements of the fast and accurate drilling of anchor hole in a coal roadway, the main mechanical factors are analyzed in theory through the establishment of PDC anchor bit rotary drilling mechanics model. The results show that the axial force of the PDC cutting tooth increases with the increase of the penetration depth, and shows the trend of first decreasing and then increasing with the increase of the cutting angle. When the friction coefficient of the coal-bearing strata is 0.20 to 0.43, the optimum cutting angle is from 15.0° to 18.3°, and the axial force and the …
Progress In The Research On Drilling Technology And Equipment In Coal Mining Areas Of China, Li Quanxin, Shi Zhijun, Tian Hongliang, Yao Ke, Liu Jianlin, Yao Yafeng, Xu Chao, Fang Jun, Liu Fei
Progress In The Research On Drilling Technology And Equipment In Coal Mining Areas Of China, Li Quanxin, Shi Zhijun, Tian Hongliang, Yao Ke, Liu Jianlin, Yao Yafeng, Xu Chao, Fang Jun, Liu Fei
Coal Geology & Exploration
Drilling technology and equipment play a key role in coalbed methane(gas) development and ensuring coal mine safe production in coal mining areas. The complicated geological and mining conditions of coal seams in China determine that the drilling technology and equipment must be based on the basic situation of coal mining areas and take the way of independent innovation. The representative achievements of drilling technology and equipment in coal mining area during the Eleventh Five-Year Plan and the Twelfth Five-Year Plan were systematically summarized in this paper. Additionally, it presents comprehensive introduction to the great achievements of surface drilling and underground …
Research On Key Technology Of The 15 000 N·M High-Power Directional Drilling Rig, Fang Peng
Research On Key Technology Of The 15 000 N·M High-Power Directional Drilling Rig, Fang Peng
Coal Geology & Exploration
According to the actual demand for ultra-long distance directional drilling in coal seam and large diameter directional drilling in seam roof, and the function of compound directional drilling technology for drilling rig, the technical idea of modular development for the functional development and design of high-power directional drilling rig are put forward. Combined with the contradiction among high-power matching, large capacity output and compact layout design of drilling rig, the key technologies of 15 000 N·m high-power directional drilling rig are researched in this paper, including overall layout design, large capacity rotary head design and layer board analysis, large opening …
Design Of Remote Control System Of Drilling Rig In Coal Mines, Weng Yinsheng, Wu Di, Lu Feifei, Wang Longpeng
Design Of Remote Control System Of Drilling Rig In Coal Mines, Weng Yinsheng, Wu Di, Lu Feifei, Wang Longpeng
Coal Geology & Exploration
In order to solve the influence of the dangerous conditions in the deep mine, such as large percus-sive ground pressure and high temperature and humidity of the roadways in deep mines on drilling operation, a remote control drilling rig control system is designed. The control system consists of local control terminal and remote control terminal, both communicating by CAN(Controller Area Network) bus and optical fiber for data and image. Local control terminal core uses automobile PLC(Programmable Logic Controller) as the control core to realize data acquisition and control, develops program in CoDeSys. The remote control terminal, based on MCU and …
Hole-Bottom Hydraulic Pressurization Technology For Directional Drilling In Hard Rock In Underground Coal Mines, Xu Baolong, Yao Ningping, Wang Li, Cao Jing, Dou Xuqian
Hole-Bottom Hydraulic Pressurization Technology For Directional Drilling In Hard Rock In Underground Coal Mines, Xu Baolong, Yao Ningping, Wang Li, Cao Jing, Dou Xuqian
Coal Geology & Exploration
In order to solve the problem of large feeding pressure, low drilling efficiency and limited hole depth caused by the backing effect of drill string during directional drilling of deep hole in underground coal mines, a technical idea of using hydraulic tool to increase WOB was proposed. The structural design of the hydraulic pressurizer at the bottom of the hole was carried out by drawing on the structure of the hydraulic pressurizer in the field of oil drilling and combining the nearly horizontal drilling conditions in underground coal mines. The hydraulic parameters were designed by the theoretical calculation and the …
Progress And Prospects Of Coal Geological Work In Tibet, Qiao Junwei, Ning Shuzheng, Song Shiyu, Yang Cheng
Progress And Prospects Of Coal Geological Work In Tibet, Qiao Junwei, Ning Shuzheng, Song Shiyu, Yang Cheng
Coal Geology & Exploration
Through the summary of the coal geological work and achievements in Tibet for nearly 70 years, the current status and main results of coal geological exploration in the main coal mines in the region were reviewed. The formation age, distribution range, coal content and coal quality characteristics of coal-bearing strata in major coal mines in the region were found out. The division of coal-bearing tectonic units and coal-accumulating basins in Tibet was summarized, and the sedimentary systems and sedimentary environments of coal-bearing strata in the main coal-forming periods were preliminarily summarized. It is generally believed that the overall degree of …
Geological Consideration For Site Selection Of Underground Coal Gasifier, Han Lei, Qin Yong, Wang Zuotang
Geological Consideration For Site Selection Of Underground Coal Gasifier, Han Lei, Qin Yong, Wang Zuotang
Coal Geology & Exploration
Underground coal gasification(UCG) is a revolution in traditional coal mining technology, and the site selection of underground coal gasifier is a prerequisite for a successful UCG project. Refining and analyzing the previous research results, the principle of UCG and the geological controls of site selection of underground coal gasifier were reviewed. The results show that lignite is the most suitable for UCG. UCG should choose thickness greater than 2 m, angle is less than 70° and buried depth of coal seam is 300 to 2 000 meters. At the same time, the UCG process may pollute the groundwater, and the …
Fracture Extension Law Of Hydraulic Fracture In Coal With Different Structure, Jia Qifeng, Ni Xiaoming, Zhao Yongchao, Cao Yunxing
Fracture Extension Law Of Hydraulic Fracture In Coal With Different Structure, Jia Qifeng, Ni Xiaoming, Zhao Yongchao, Cao Yunxing
Coal Geology & Exploration
To find out the fracture extension law of coal hydraulic fracturing with different coal body structures can lay a foundation for reasonable well pattern deployment. Taking Shizhuang block of Qinshui basin as the research object, the fracture of coal core was observed, and four kinds of coal with fracture development degree were divided. Based on the theory of rock mass mechanics, the stress field calculation model of fracture tip and the judgment criterion of whether hydraulic fracture can pass through natural fracture in hydraulic fracturing process were established. According to the measured data of CBM wells, the reliability of theoretical …
Study On Pore Structure And Pressure-Sensitive Effect Of Tectonic Coal In Huaibei Xutuan Mine, Dong Kui, Jia Jiancheng, Gong Zewen, Wu Yan
Study On Pore Structure And Pressure-Sensitive Effect Of Tectonic Coal In Huaibei Xutuan Mine, Dong Kui, Jia Jiancheng, Gong Zewen, Wu Yan
Coal Geology & Exploration
In order to discuss pore structure and pressure-sensitive effect of tectonic coal, coal samples of Huaibei Xutuan mine were measured by optical microscope, scanning electron microscope, mercury injection, and triaxial servo-controlled seepage equipment for thermo-fluid-solid coupling to reveal the pore structure and the influence of effective stress on permeability or permeability coefficient of structural coal. The results show that cataclastic structure of tectonic coal is regular, flat and has good connectivity; the pores of primary coal are mainly composed of micropores, micropores and transitional pores are dominant in tectonic coal has. The effective stress of ductile deformed coal has a …
Preparation Of Polished Slice Of Special Coal And Its Influence On Coal Petrology Analysis, Liu Shande
Preparation Of Polished Slice Of Special Coal And Its Influence On Coal Petrology Analysis, Liu Shande
Coal Geology & Exploration
Coal petrology analysis is widely used in coal facies research, geological exploration and coal blending test. Qualified polished coal slice is the premise of coal petrology analysis. In order to solve the preparation problem of special coal optical plates, such as brittle samples and aging coal optical plates, a complete preparation process was raised, and the feasibility of the process was verified. The results showed that Rmax was very little affected by secondary preparation, but the maceral group composition content was significantly affected, and the fluctuation of the anthracite' microcomponent was the greatest. When the maceral group composition quantification …
Analysis Of Diffusion Properties Of Methane In Low Rank Coal, Meng Zhaoping, Zhang Guiyuan, Li Guoqing, Liu Jinrong
Analysis Of Diffusion Properties Of Methane In Low Rank Coal, Meng Zhaoping, Zhang Guiyuan, Li Guoqing, Liu Jinrong
Coal Geology & Exploration
Diffusion properties of methane in coal is an important reservoir parameter affecting CBM production. Using the lignite samples from the Xiaolongtan Formation of the Miocene Neogene in southeastern Yunnan Province, the isothermal adsorption experiments of methane in low rank coal were carried out. Based on the relationship between adsorption amount and time obtained from isothermal adsorption experiment, the diffusion coefficient of methane in coal was calculated by using an unipore model of unsteady gas diffusion. The diffusion law of methane in coal and its control mechanism were revealed. The results show that gas diffusion law in coal obeys Langmuir equation; …
Reservoir-Forming Conditions Of Shale Gas In Badaowan Formation In Fukang Area, Xinjiang, Zhang Min, Li Xianqing, Zhang Jizhen, Sun Jie, Liang Wanle, Duan Zhiyou, Li Hanqing
Reservoir-Forming Conditions Of Shale Gas In Badaowan Formation In Fukang Area, Xinjiang, Zhang Min, Li Xianqing, Zhang Jizhen, Sun Jie, Liang Wanle, Duan Zhiyou, Li Hanqing
Coal Geology & Exploration
In order to evaluate the potential of shale gas of coal measures in Fukang area, Xinjiang, taking the shale of Jurassic coal measures in Badaowan Formation as an example, the study was carried out and the favorable accumulation area for shale gas was preliminarily put forward according to the drilling, core data and sample analysis results in this paper. The result shows that the accumulative thickness of Jurassic Badaowan Formation shale is big(200-400 m), the buried depth is shallow(<1 500 m), the organic carbon content is high(average TOC>2.0%), mainly of type Ⅲ and Ⅱ2, thermal evolution level is moderate(Rran is 0.8%-1.1%, mature), physical property of reservoir …
Modification Of Na-K-Mg Triangular Diagram And Selection Of Na-K Geothermometer, Wang Xin, Qi Jihong, Xu Mo, Ma Xiaoyun
Modification Of Na-K-Mg Triangular Diagram And Selection Of Na-K Geothermometer, Wang Xin, Qi Jihong, Xu Mo, Ma Xiaoyun
Coal Geology & Exploration
Na-K-Mg triangular diagram is a preliminary method of determining the water-rock equilibrium state. It does not specifically consider the effect of geothermometer equations and mineral compositions on the equilibrium state. Therefore, using the Na-K-Mg triangular diagram modified by different Na-K geothermometer equations to judge water-rock equilibrium state, and using the suitable Na-K geothermometer equation to calculate the temperature of geothermal reservoirs, is of great significance to divide the genetic types of geothermal systems and develop or utilize geothermal resources. It is found that any point in the modified Na-K-Mg triangular diagram is fully equilibrated with the curve determined by one …
Coal Mine Water Inrush Prediction Based On Lstm Neural Network, Dong Lili, Fei Cheng, Zhang Xiang, Cao Chaofan
Coal Mine Water Inrush Prediction Based On Lstm Neural Network, Dong Lili, Fei Cheng, Zhang Xiang, Cao Chaofan
Coal Geology & Exploration
According to the prediction of water inrush from coal seam floor, based on the summarization of existing water inrush prediction methods and theories, the feature selection experiment shows that water pressure, distance from the working surface, sandstone section thickness, coal thickness, coal seam inclination, fault throw, fissure zone, mining area, mining height and strike length are the main factors affecting the occurrence of water inrush. These factors are complex and non-linear. A water inrush prediction model based on long short-term memory(LSTM) neural network was proposed. The data of the coal mine water inrush case was used as sample data to …
Influence Of Composite Roof Structure On The Stability Of Coal Roadway, Chen Xinnian, Wang Jingchun, Xiong Xianyu, Fan Jiawei, Shen Pan
Influence Of Composite Roof Structure On The Stability Of Coal Roadway, Chen Xinnian, Wang Jingchun, Xiong Xianyu, Fan Jiawei, Shen Pan
Coal Geology & Exploration
The composite roof structure of coal roadway is rather complex. Its stability is related to lithology, thickness of strata, number of strata, location of strata and cohesive force between layers. Based on mechanics theory of simplified composite roof composite beams, a simplified mechanical test model of composite beams was established, and the effects of the structural characteristics of composite roof on the stability of composite beams were analyzed by experiments. The purpose is to provide a scientific basis for the classification and control of composite roof stability. The results show that the stability of the roof increases with the increase …
Numerical Analysis Of Temperature Field Of Underwater Dredging Artificial Frozen Plate, Wu Yuwei, Hu Jun, Wang Zhixin, Zeng Dongling, Wang Shucheng
Numerical Analysis Of Temperature Field Of Underwater Dredging Artificial Frozen Plate, Wu Yuwei, Hu Jun, Wang Zhixin, Zeng Dongling, Wang Shucheng
Coal Geology & Exploration
In order to understand the development of the temperature field of artificial freeze dredging plates and the process of the formation of frozen curtains, the finite element analysis was used to perform numerical analysis using the single factor analysis method for research of the frozen process in different circumstances of geometric size of plate and physical environment of the soil under water. The results show that the correlation between the different geometric dimensions of the frozen plate and the dredging depth is weak, and the geometric dimension of the frozen plate can only change the area of dredging; for the …
Study On Complex Resistivity Of Artificial Sandstone Containing Conductive Mineral Under High Pressure, Tian Gang, Tang Xingong, Xiang Kui, Chi Meiyao
Study On Complex Resistivity Of Artificial Sandstone Containing Conductive Mineral Under High Pressure, Tian Gang, Tang Xingong, Xiang Kui, Chi Meiyao
Coal Geology & Exploration
Due to the complex pore structure and non-single skeleton composition, natural rock samples are more difficult to study than artificial rock samples. The standard rock samples with different mineral content and volume content were artificially synthesized by using brass powder, pyrite sand, graphite powder, epoxy resin, etc. Complex resistivity measurements were taken to the samples by using AutoLab-1000 equipment under different formation pressure conditions. The complex resistivity and the parameters of zero frequency resistivity, polarizability, and time constant of the artificial sandstone standard were derived based on Debye decomposition model. Made a discussion on relationship between parameters of the model, …
Properties Of Mud Cake Associated With Silica Shale Powder Intrusion Into Drilling Fluid, Mo Dingqiang, Sun Pinghe, Zhao Binkui, Wang Jingyuan, Zhang Shaohe, Cao Han
Properties Of Mud Cake Associated With Silica Shale Powder Intrusion Into Drilling Fluid, Mo Dingqiang, Sun Pinghe, Zhao Binkui, Wang Jingyuan, Zhang Shaohe, Cao Han
Coal Geology & Exploration
Drilling fluid is very important for maintaining the stability of the hole wall in shale drilling. The mud cake formed by the fluid loss also plays a decisive role in protecting the reservoir. In order to study the influence of shale rock powder intrusion into low-solid-phase drilling fluids on the basic properties of mud cakes, the paper selects the siliceous shale powders in northwestern Hunan as the research object, and designs orthogonal experiments. In addition, the test results are analyzed using variance and range, which show that the content of rock powder is the main factor affecting the thickness of …
Theoretical Research On The Ploughing Rock Breaking Properties Of New Conical Pdc Cutter, Ju Pei, Wang Chuanliu
Theoretical Research On The Ploughing Rock Breaking Properties Of New Conical Pdc Cutter, Ju Pei, Wang Chuanliu
Coal Geology & Exploration
The researches on the conical PDC cutter are now focused on numerical simulation, field and laboratory tests, the theoretical analysis on its mechanical properties has not been reported. Therefore, the tensile shear rock breaking mechanism and cutting load distribution characteristics of the conical PDC cutter are described by numerical simulation, the theoretical formula of the cutting load is derived according to the energy balance principle. Results show that comparing with the conventional cylindrical PDC cutter, the rock breaking process of conical PDC cutter is more stable, the cutting load is influenced by the rock properties, the parameters of cutter structure, …
Adsorbability Of Shale In Coal Measures And Its Influencing Factors, Zhang Baoxin, Fu Xuehai, Zhang Qinghui, Zhou Baoyan, Liu Zheng
Adsorbability Of Shale In Coal Measures And Its Influencing Factors, Zhang Baoxin, Fu Xuehai, Zhang Qinghui, Zhou Baoyan, Liu Zheng
Coal Geology & Exploration
In order to reveal the adsorption and gas-bearing characteristics of shale in coal measures, this study was based on the gas content, isotherm adsorption, high-pressure mercury injection, and liquid nitrogen adsorption of more than 200 coal shale in six major coal fields in Shanxi Province and Junggar basin. XRD diffraction and other measured data, the adsorption and gas characteristics of shale were analyzed, and the influencing factors were discussed. The results show that the measured gas content of shale is between 0-5.87 cm3/g, concentrated at 0.90-2.00 cm3/g; VL is between 0.11-6.3 cm3/g with …
Distribution Characteristics Of Associated Elements In Middle Jurassic Coal In The North Of Datong Coalfield And Their Geological Significance, Qu Xiaorong
Coal Geology & Exploration
In order to study the geochemical characteristics and geological significance of associated elements in Middle Jurassic coal of Datong coalfield, the distribution and occurrence of the associated elements in 9 coal seams in the northern Datong coalfield were analyzed by inductively coupled plasma mass spectrometry(ICP-MS), X-ray diffraction(XRD), optical electron microscopy and scanning electron microscopy(SEM). The results show that the Jurassic coal in Datong coalfield has low trace element content, and beneficial elements(Li, Ga) are far lower than the boundary grade, which has no development potential. But the harmful elements such as Co and Zn in No.2 coal, Tl in No.9, …
Storage Rule And Controlling Factors Of Coalbed Gas In Zhaoguan Mine Field Of Huanghebei Coalfiled, Song Xiaozhong
Storage Rule And Controlling Factors Of Coalbed Gas In Zhaoguan Mine Field Of Huanghebei Coalfiled, Song Xiaozhong
Coal Geology & Exploration
Storage rule and controlling factors of coalbed gas in Zhaoguan mine field were analyzed on the basis of the generation, storage and migration theory of coalbed gas in combination with the data of geological exploration and mine production. From research on the regional geological evolution, coal generating and storing capacity and lithologic characteristics, geological structure, burial depth, bedrock thickness, hydrogeological conditions and magmatic intrusion, it was found that underground hydrodynamic conditions and magmatic intrusion events are the controlling factors of coalbed gas storage in the mine. Underground hydrodynamic conditions had obvious effect, shallow hydrodynamic conditions were manifested mainly as migration …
Slope Stability Evaluation Based On Set Pair Cloud Model, Yao Jianye, Zhang Shan, Hao Guoqiang
Slope Stability Evaluation Based On Set Pair Cloud Model, Yao Jianye, Zhang Shan, Hao Guoqiang
Coal Geology & Exploration
When the set pair analysis is applied to evaluate slope stability, the connection degree is usually decided by linear function, which can't reflect the actual conditions of the engineering project objectively and comprehensively and neglect the system randomness. The set pair analysis theory is improved by application of cloud theory which is superior in dealing with the connection degree and set pair analysis-cloud model of slope stability evaluation is established. In this model, the weight matrix is obtained by using the cloud theory to improve the AHP, and the evaluation matrix is obtained by combining with the connection degree evaluation …
Microseismic Positioning Method Based On Differential Evolution Algorithm, Wang Yunhong, Wang Baoli, Duan Jianhua
Microseismic Positioning Method Based On Differential Evolution Algorithm, Wang Yunhong, Wang Baoli, Duan Jianhua
Coal Geology & Exploration
Aiming at the problem that the location accuracy of conventional time-based microseismic location method depends on the accuracy of travel time, a differential evolution microseismic location method is proposed to improve the locating target function. Based on the traditional micro-seismic P-wave travel-time location method, the error weighting coefficient was added to the localization objective function, which reduced the impact of the first-time picking accuracy on the microseismic location by reducing the effect of the microseismic signal path with low initial pick-up accuracy on the locating error. The differential evolution algorithm, through population initialization, mutation, crossover, and selection operations, solves the …