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Genesis Analysis And Study On Tectonic Control On Water Of Huainan North China-Type Coal Field, Ding Tongfu, Wang Minhua, Zhao Junfeng Aug 2020

Genesis Analysis And Study On Tectonic Control On Water Of Huainan North China-Type Coal Field, Ding Tongfu, Wang Minhua, Zhao Junfeng

Coal Geology & Exploration

In order to analyze deeply the genesis and tectonic control on water of the macrostructures of the fourth stage of the Huainan North China-type coalfield, the forms of folds and faults of the Huainan coalfield were used to verify and compare the North China craton geohistory, stratigraphy, and regional tectonics. Quantitative evaluation of the impact of mining area 8 on production mines was conducted. The results show that the Huainan coalfield was formed by the superposition of the Indosinian, Yanshan and Himalayan movements. The Indosinian movement formed the Huainan coalfield at near-east-west tectonic line(body) in the first stage, and the …


Geochemical Characteristics Of Elements In The Paleogene Yunlong Formation And The Restoration Of Paleoenvironment In Lanping Basin, Liu Xiaokang, Zhang Zhibo, Zhu Zhijun, Wu Chuanfu, Wei Xingxing, Liu Haiyan, Jin Tengrui, Baima Quzong Aug 2020

Geochemical Characteristics Of Elements In The Paleogene Yunlong Formation And The Restoration Of Paleoenvironment In Lanping Basin, Liu Xiaokang, Zhang Zhibo, Zhu Zhijun, Wu Chuanfu, Wei Xingxing, Liu Haiyan, Jin Tengrui, Baima Quzong

Coal Geology & Exploration

In order to restore the sedimentary environment of the Paleogene Yunlong Formation in the Lanping basin, inductively coupled plasma mass spectrometry(ICP-MS) was used to analyze trace elements in 13 samples of gypsum, limestone, gypsum mud, mudstone and sandstone from the Paleogene Yunlong Formation in Lanping Basin. The sedimentary environments and paleoclimate are estimated based on the spider diagram of trace elements in each lithology and the characteristics of the ratio of Cu/Zn, Sr/Cu and Sr/Ba and the content of Sr. The results show that:gypsum, limestone, gypsum mud, mudstone and sandstone are all rich in Rb, Pb, Zr; gypsum and gypsum …


Applicability Of Mercury Injection Test To The Characterization Of Low Rank Coal And Its Correction Method, Liu Yinan, Liu Yong, Xin Fudong, Wei Hongyu Aug 2020

Applicability Of Mercury Injection Test To The Characterization Of Low Rank Coal And Its Correction Method, Liu Yinan, Liu Yong, Xin Fudong, Wei Hongyu

Coal Geology & Exploration

As an effective method for coal reservoir characterization, mercury intrusion has been widely used in reservoir property analysis of medium-high rank coal. However, for low-rank coal, due to its loose and brittle nature, the process of mercury intrusion will destroy the pore structure, resulting in poor applicability of mercury intrusion experiments. In order to accurately assess the damage to the pore structure of low-rank coal by mercury intrusion experiments, lignite and long flame coal were selected as the research objects, and the pore size distribution of coal was tested by mercury intrusion and nuclear magnetic resonance. The results show that …


Biogas Production And Variation Of The Chemical Composition Of The High Temperature Water Extract Of Lignite, Ren Hengxing, He Huan, Liu Fangjing, Wang Meilin, Guo Xin, Chen Linyong, Zhao Han, Yuan Xuefang, Guan Jiadong, Yue Lijiao Aug 2020

Biogas Production And Variation Of The Chemical Composition Of The High Temperature Water Extract Of Lignite, Ren Hengxing, He Huan, Liu Fangjing, Wang Meilin, Guo Xin, Chen Linyong, Zhao Han, Yuan Xuefang, Guan Jiadong, Yue Lijiao

Coal Geology & Exploration

The interaction process between microorganism and coal is complicated. In order to deeply analyze the function and change rule of organic matter in coal in the process of biological gas production, taking Yima lignite and methanogens preserved in laboratory as research objects, the gas production characteristics of water-soluble organic matter of lignite and its chemical composition change before and after gas production were studied. The water-soluble organic components of Yima lignite obtained by deionized water extraction at 70℃ and the extraction residue were used as substrates for biogas production. High performance liquid chromatography-mass spectrometry (HPLC-MS), gas chromatography(GC) and gas chromatography-mass …


Application Of Controllable Electric Pulse Wave Permeability-Enhancing Technology In The Low-Permeability Coal Seams, An Shigang, Chen Dianfu, Zhang Yongmin, Kong Delei, Li Yang, Zhang Di, Wang Yang Aug 2020

Application Of Controllable Electric Pulse Wave Permeability-Enhancing Technology In The Low-Permeability Coal Seams, An Shigang, Chen Dianfu, Zhang Yongmin, Kong Delei, Li Yang, Zhang Di, Wang Yang

Coal Geology & Exploration

Controllable electric pulse wave permeability-enhancing technology is one of the ideal measures for anti-reflection transformation of low-permeability coal seams. The optimization of construction schemes needs to be solved urgently. Aiming at this problem, in the low-permeability coal seam of Baode coal mine, controllable electric pulse wave permeability-enhancing technology was adopted to optimize the permeability-enhancing construction scheme of the boreholes. Test results show that the controllable electric pulse wave permeability-enhancing effect is the best under the condition of the average permeability-enhancing section of 131 m, the impact density of 0.5 times/m and the average daily extraction volume in an anti-reflection borehole …


Geochemical Characteristics And Their Origin Of Cbm In Xingxian Area, Ordos Basin, Wang Xiangye, Sun Baoping Aug 2020

Geochemical Characteristics And Their Origin Of Cbm In Xingxian Area, Ordos Basin, Wang Xiangye, Sun Baoping

Coal Geology & Exploration

The distribution of carbon and hydrogen isotope of methane is of signification in revealing the origin, the distribution of CBM reservoir, and the source evaluation of CBM. To study the origins of coalbed methane and carbon dioxide, the data of the components、carbon and hydrogen isotopes of CBM from the desorption gas of coal core from Xingxian area were analyzed. With the CBM origins chart board, and the geological environment, the geological effect of the formation and the evolution of CBM were analyzed. the ratios of CBM with different origins were estimated. The results show that the δ13C, values …


Corrosion And Degradation Of Feldspar Sandstone In Acidic Environment, Zhou Bin, Zhang Dongming, Xu Jiang, Cheng Liang, Li Jiaxin Aug 2020

Corrosion And Degradation Of Feldspar Sandstone In Acidic Environment, Zhou Bin, Zhang Dongming, Xu Jiang, Cheng Liang, Li Jiaxin

Coal Geology & Exploration

In order to study the effect of acidic environment on the corrosion and deterioration of rocks, CT images processing technology was used to analyze the meso-composition and structural changes of feldspar sandstone after soaking in acidic water. Shimadzu AGI-250 servo material testing machine was used to carry out uniaxial compression test to observe the deterioration of mechanical parameters. The results show that the total density of the feldspar sandstone decreased Ofter the acidic environment treatment, the distribution trend is homogeneous, and the mineral with higher density is formed in the local area. The secondary pores of the feldspar sandstone increased …


Overburden Failure Simulation Under Double Coal Seams Mining In A Coal Mine In North Shaanxi Province, Sun Xueyang, Zhang Qi, Li Cheng, Zhang Lei Aug 2020

Overburden Failure Simulation Under Double Coal Seams Mining In A Coal Mine In North Shaanxi Province, Sun Xueyang, Zhang Qi, Li Cheng, Zhang Lei

Coal Geology & Exploration

Under the conditions of multi-seam mining, the overburden failure of coal seams has unique characteristics, which affects the mine production arrangement. Taking a mine in northern Shaanxi Province as an example, based on the geological and mining conditions of the mine, the influence of double-seam mining on overburden rock damage was analyzed by using the method of similar material simulation experiment and numerical simulation. The results show that the height of the caving zone and the height of the fractured zone in the overburden of coal seam obtained by using similar material simulation and numerical simulation with different widths of …


Sensitivity Analysis Of Disaster-Pregnant Environmental Factors For Slope Geological Hazards In Kaiyang County, Guizhou Province, Qin Yigen, Yang Genlan, Xie Jin, Liu Bangyu Aug 2020

Sensitivity Analysis Of Disaster-Pregnant Environmental Factors For Slope Geological Hazards In Kaiyang County, Guizhou Province, Qin Yigen, Yang Genlan, Xie Jin, Liu Bangyu

Coal Geology & Exploration

The geological conditions are complex in Kaiyang County, and geological disasters occur frequently. On the basis of field geological hazard investigation, 8 factors including elevation, slope, slope direction, engineering petrofabric, slope structure, fault, drainage and NDVI value are selected as the disaster-pregnant factors of slope geohazards. Based on the GIS platform, and by using the certainty factor model(CF) and the sensitivity-exponential(E), susceptibility of these 8 factors are researched. The results show that the areas with elevation from 515 to 993 m, the slope degree from 20° to 50°, the aspect of the west, the northwest and the southeast, …


Spatial Distribution Of Soil Nutrients In Reclamation Dump Sites Based On Subdivision Idw, Zhao Yanling, Zhao Bincheng, Wang Xin, Xiao Wu, Liu Huifang Aug 2020

Spatial Distribution Of Soil Nutrients In Reclamation Dump Sites Based On Subdivision Idw, Zhao Yanling, Zhao Bincheng, Wang Xin, Xiao Wu, Liu Huifang

Coal Geology & Exploration

Accurately grasping the spatial distribution of soil nutrients is of great significance for evaluating the soil quality of reclamation dumps and formulating corresponding reclamation measures. The general interpolation method of the complex terrain of the dump site has a poor prediction effect. The northern dump of Shengli No.1 open-pit mine in Xilinhot, Inner Mongolia was selected as an example in the paper. The soil nutrients(available nitrogen, available potassium, available phosphorus and organic matter) were spatially interpolated using the inverse distance weighting method based on terrain partitioning, and compared with the conventional inverse distance weighting method and kriging interpolation method. The …


Study On The Effect Of Dual-Freedom Coupling Between The Tilt Geophones And The Surface, Sun Chao, Sun Liang, He Dengke, Tian Siqing Aug 2020

Study On The Effect Of Dual-Freedom Coupling Between The Tilt Geophones And The Surface, Sun Chao, Sun Liang, He Dengke, Tian Siqing

Coal Geology & Exploration

In the process of coalfield seismic data acquisition, there is a situation of repeated geophone layout at the same point. The tilt angle difference of the geophones will leads the change of coupling condition between the geophone and the surface, which affects the quality of seismic data acquisition. In this paper, the tilt angle parameters of geophone were introduced into the coupling system of the geophone and the surface. From the point of view of vibration mechanics, the "vibration system with coupling of the dual degree of freedom" of tilt geophone was deduced. The influences of the tilt angle of …


The High-Resolution Transient Electromagnetic Detection Technology For Ultra-Shallow Layer In Coal Mine, Zhang Jun Aug 2020

The High-Resolution Transient Electromagnetic Detection Technology For Ultra-Shallow Layer In Coal Mine, Zhang Jun

Coal Geology & Exploration

In order to reduce the blind zone of the transient electromagnetic detection in mines and improve the detection accuracy, the high-resolution transient electromagnetic detection technology for the ultra shallow layer in mines is studied. The high-resolution transient electromagnetic detection technology for ultra-shallow layer in mines is not only suitable for conventional mine geological exploration, but also for high-resolution detection of shallow geological bodies such as cracks in the roof of the mine roadway, ensuring the safe and efficient mining. Through theoretical research, the feasibility of the shallow high-resolution transient electromagnetic method in mine was established; the hardware system of the …


Design Of Piezoelectric Effect-Based Energy Recovery Device Wile Drilling, Wu Tianyu, Zheng Jun, Zhang Bo, Chen Yu, Tian Hong, Dou Bin Aug 2020

Design Of Piezoelectric Effect-Based Energy Recovery Device Wile Drilling, Wu Tianyu, Zheng Jun, Zhang Bo, Chen Yu, Tian Hong, Dou Bin

Coal Geology & Exploration

Aiming at the problem of continuous power supply of downhole instruments and the recovery of longitudinal vibration energy of drill pipe in drilling field, a new type of energy recovery device based on positive piezoelectric effect was designed. The radial dimension parameters and piezoelectric materials were designed by field experiences and geological survey reports. The piezoelectric coupling model was established based on the numerical simulation software COMSOL Multiphysics, and the length range and the best installation position of the piezoelectric plate were obtained through forced vibration analysis. Through modal analysis and frequency response research, it is obtained that the natural …


Waveform Cross Correlation-Based Imaging Of Underground Seismic Data While Mining, Zhang Huanlan, Wang Baoli Aug 2020

Waveform Cross Correlation-Based Imaging Of Underground Seismic Data While Mining, Zhang Huanlan, Wang Baoli

Coal Geology & Exploration

Seismics while mining is a passive seismic detection technique using a shearer as seismic source. Because the shearer moves unceasingly and excites the continuous signals, the conventional data processing method cannot be applied directly. In the paper a cross-correlation method of segmented waveform was put forward, the effective signal travel time was extracted through the segmentation of the data generated the shear, and then the velocity imaging method was used to image the interior of the working face and the front of the cutting hole. The wave equation was used to carry out the seismics while mining numerical simulation of …


Model And Selection Criterion Of Zonal Preact Grouting To Prevent Mine Water Disasters Of Coal Floor Limestone Aquifer In North China Type Coalfield, Dong Shuning, Guo Xiaoming, Liu Qisheng, Wang Hao, Nan Shenghui, Zheng Shitian, Wang Yuhang Aug 2020

Model And Selection Criterion Of Zonal Preact Grouting To Prevent Mine Water Disasters Of Coal Floor Limestone Aquifer In North China Type Coalfield, Dong Shuning, Guo Xiaoming, Liu Qisheng, Wang Hao, Nan Shenghui, Zheng Shitian, Wang Yuhang

Coal Geology & Exploration

In order to promote the development of zonal preact grouting technology and establish a system of the technology to prevent mine water disasters of coal floor aquifer, the authors analyze and summarize the coal seam occurrence and hydrogeological conditions of the Carboniferous-Permian coalfields in China, starting from the engineering systematicity, focusing on the three main factors of drilling conditions, grouting layer selection and drilling technology in the engineering of zonal preact grouting to prevent mine water disasters of coal floor aquifer. The model of zonal preact grouting to prevent mine water disasters of coal floor aquifer is established, which can …


Integrated Monitoring Technology Of Water Inrush From Coal Seam Floor And Its Application, Duan Jianhua Aug 2020

Integrated Monitoring Technology Of Water Inrush From Coal Seam Floor And Its Application, Duan Jianhua

Coal Geology & Exploration

Karst water damage in floor is a common problem in North China type coalfield. Because of its characteristics of concealment and emergency, the prevention and control of water is faced with huge problems and challenges, monitoring and early warning technology of floor water inrush has become a necessary measure in the process of the safe production in coal mines. The formation and occurrence of floor water disaster have a process of evolution from conception, development to occurrence. In this process, the corresponding water inrush symptoms will be released in different stages of the floor crack and apparent resistivity of the …


Application Of Borehole Transient Electromagnetic Detection In The Test Of Hydraulic Fracturing Effect, Zhao Rui, Fan Tao, Li Yuteng, Wang Jikuang, Ma Yuan, Wang Bingchun, Liu Lei, Fang Zhe Aug 2020

Application Of Borehole Transient Electromagnetic Detection In The Test Of Hydraulic Fracturing Effect, Zhao Rui, Fan Tao, Li Yuteng, Wang Jikuang, Ma Yuan, Wang Bingchun, Liu Lei, Fang Zhe

Coal Geology & Exploration

Hydraulic fracturing technology is widely used in various aspects such as mine rock burst prevention and surrounding rock depressurization, but there has been a lack of efficient and intuitive technology for evaluating the fracturing effectiveness. To solve this problem, a three-component borehole TEM detection method using dynamic source and reception unit was proposed, and detection equipment and supporting construction techniques suitable for construction in hydraulic fracturing holes were developed. Two engineering tests have been carried out in a coal mine. By comparing the processing results of the vertical components of the two detection data before and after fracturing, a pure …


Construction Technology Of Vertical Concealed Laying Of Anti-Seepage Membrane For Water Cutoff Curtain In The Open-Pit Coal Mine, Li Wensong, Dang Yakun, Zhu Mingcheng, Gao Ya Aug 2020

Construction Technology Of Vertical Concealed Laying Of Anti-Seepage Membrane For Water Cutoff Curtain In The Open-Pit Coal Mine, Li Wensong, Dang Yakun, Zhu Mingcheng, Gao Ya

Coal Geology & Exploration

Anti-seepage membrane(HDPE geomembrane) is widely used in anti-seepage projects currently that mainly prevent pollution, leakage and diffusion, and its laying form was various. In an underground water cutoff curtain project of an open-pit coal mine in China, the anti-seepage membrane was laid vertically as the main body of the water cutoff curtain wall, and the largest concealed depth was about 50 m. The different groove sections was overlapping connected by using connection box technology. Through the grouting and backfilling process, the impermeability of the curtain wall was improved and the anti-seepage membrane was compacted. Finally, pumping test in the surrounding …


Water Absorption Characteristics And Their Influence On The Mechanical Properties Of Longmaxi Formation Shale In Northeastern Chongqing, Liu Hong, Xu Fenglin, Chen Qiao, Zhu Honglin, Su Degui, Feng Kelai Aug 2020

Water Absorption Characteristics And Their Influence On The Mechanical Properties Of Longmaxi Formation Shale In Northeastern Chongqing, Liu Hong, Xu Fenglin, Chen Qiao, Zhu Honglin, Su Degui, Feng Kelai

Coal Geology & Exploration

A certain amount of casing deformation occurs during the shale reservoir fracturing. There is a certain amount of clay minerals in shale, and after contacting with water-based fracturing fluid, it will show the same expansion characteristics and strength weakening effect as mudstone, which will increase the casing external load. Aiming at the Longmaxi Formation shale in the northeast of Chongqing, the self-absorption and swelling characteristics of shale under different solution systems are studied by physical experiments to analyze the effect of shale hydration on its rock mechanical properties. The results show that the water absorption of shale has a logarithmic …


Reasons Of Low Yield And Stimulation Measures For Cbm Wells In Junlian Area, Li Ying, Zheng Rui, Luo Kai, Zhu Yanming, Zhang Yimin Aug 2020

Reasons Of Low Yield And Stimulation Measures For Cbm Wells In Junlian Area, Li Ying, Zheng Rui, Luo Kai, Zhu Yanming, Zhang Yimin

Coal Geology & Exploration

Coalbed methane fields in Junlian area have good development potential, but the existence of a large number of low-production and low-efficiency wells has restricted the increase of productivity. This paper analyzes the coupling relationship between high-productivity wells and geological factors from the perspective of geological engineering integration, analyzes the causes of inefficient wells from three aspects of geology, drainage and engineering, and evaluates the corresponding reform measures. The results show that the formation of inefficient wells in the north and the west of the study area is mainly affected by gas-bearing properties, fault distribution, production horizons, production and drainage rhythms, …


Development Characteristics Of Freezing Temperature Field Of Coastal Soft Soil Strata, Chen Junhao, Zhuang Yan, Chen Bijian, Zhao Zhenwei, Wang Qiyun Aug 2020

Development Characteristics Of Freezing Temperature Field Of Coastal Soft Soil Strata, Chen Junhao, Zhuang Yan, Chen Bijian, Zhao Zhenwei, Wang Qiyun

Coal Geology & Exploration

In order to research the temperature fields and development law of freezing in the construction of connected aisle in coastal soft soil stratum, based on connected aisle between Luoxiu road station and Baise road station of Shanghai subway Line 15, the thickness and average temperature of frozen curtain, and the freezing process were analyzed. The temperature fields and development law of freezing were predicted by the three-dimensional numerical model of the connected aisle and the temperature data which were analyzed. The results show that the inherent pressure in soft soil causes initial pressure in the pressure relief hole. A lot …


Collapse Column Identification Method Based On Seismic Waveform Indication Inversion And Its Application, Wan Zhaofei, Guo Zenghu, Wang Peng, Tang Meizhen, Han Tianbao, Liu Liangqiong Aug 2020

Collapse Column Identification Method Based On Seismic Waveform Indication Inversion And Its Application, Wan Zhaofei, Guo Zenghu, Wang Peng, Tang Meizhen, Han Tianbao, Liu Liangqiong

Coal Geology & Exploration

During the CBM exploration and development, the collapse column is one of the important factors restricting the exploration effectiveness of coalbed methane. Therefore, the effective identification of collapse column is of great significance for the improvement of CBM exploration. The previous identification methods are based on the discontinuity of the in-phase axis of seismic reflection caused by collapse column. In this paper, the collapse column is innovatively regarded as a kind of geological anomaly, and the identification and prediction of the collapse column are attempted by means of waveform indication inversion. Firstly, through the analysis of logging data and geological …


Experimental Study On The Frequency Dispersion Response Of Composite Electrical Properties Of Coal, Meng Hui, Li Jian, Lei Dongji, Wang Yajuan Aug 2020

Experimental Study On The Frequency Dispersion Response Of Composite Electrical Properties Of Coal, Meng Hui, Li Jian, Lei Dongji, Wang Yajuan

Coal Geology & Exploration

In order to study the characteristics of frequency dispersion response of the composite electrical properties of coal, the real part R and imaginary part X of the composite resistance of coal body at different direction in different measured areas were measured, the frequency dispersion characteristics were analyzed, different classical models were used to conduct data inversion and comparison. The results show that the composite electrical property parameters(absolute value of R and X) of coal are inversely proportional to the measured area, the characteristic frequency points are not offset, the X-frequency divergence decreases with the increase of measurement area; …


Research Status And Prospect Of Drill Pipe Thread Used In Coal Mine, Tian Dongzhuang, Chen Yanyu, Li Qing, Dong Mengmeng, Mou Peiying Aug 2020

Research Status And Prospect Of Drill Pipe Thread Used In Coal Mine, Tian Dongzhuang, Chen Yanyu, Li Qing, Dong Mengmeng, Mou Peiying

Coal Geology & Exploration

Drill pipe is one of the main device for drilling construction of gas drainage, water detection and drainage and geological exploration. Due to complicated force conditions and using environment of drill pipe, accidents in boreholes caused by the failure of drill pipe threads are common. According to different structural classification, the characteristics of drill pipe thread structure in coal mines are introduced in detail; the current research status of thread stress distribution and failure analysis of thread are summarized. The research methods of thread stress distribution mainly include analytical method, finite element method and test method. The main causes of …


Water Environment Comprehensive Forewarning For Waterlogged Area In Huainan Based On Weber-Fechner Law, Pei Wenming, Zhang Hui, Ju Changhua, Yao Suping, Ren Yongle, Ma Mengxiao, Qiu Kuanbiao Jun 2020

Water Environment Comprehensive Forewarning For Waterlogged Area In Huainan Based On Weber-Fechner Law, Pei Wenming, Zhang Hui, Ju Changhua, Yao Suping, Ren Yongle, Ma Mengxiao, Qiu Kuanbiao

Coal Geology & Exploration

In area with high groundwater level in the east of China, long-time underground coal mining results in a large subsidence water area on the surface. The risk of water environment pollution in subsidence waters is increasing gradually with the influence of human activities. According to Weber-Fisher law, this paper took Panji waterlogged area of Huainan as the research object, selected the water quality evaluation indexes closely related to the water environment of the waterlogged area, analyzed the water environmental conditions of the waterlogged area in different periods, and quantitatively reflected the time and the area of the water environment quality …


Performance Test And Proportioning Optimization Of Loess-Based Grouting Materials In Coal Mining Subsidence Area Of Northern Shaanxi, Cao Xiaoyi, Wang Yutao, Liu Xiaoping, Cao Zubao, Wu Boqiang Jun 2020

Performance Test And Proportioning Optimization Of Loess-Based Grouting Materials In Coal Mining Subsidence Area Of Northern Shaanxi, Cao Xiaoyi, Wang Yutao, Liu Xiaoping, Cao Zubao, Wu Boqiang

Coal Geology & Exploration

Grouting is the main treatment method of mining subsidence area, and the grouting materials have great influence on the grouting effect and cost. Taking the grout mix composed of loess and cement used in northern Shaanxi as the research object, the viscosity, the gelation time, the stone rate and 28 d uniaxial unconfined compressive strength of loess grout were studied by single factor and orthogonal tests. The influencing factors and changing rule of each index were analyzed. Meanwhile, the GA-BPNN prediction model of loess-based grout was established, and the multi-objective global optimization was carried out through GA. The grout ratio …


Stacking Angle Of Slurry-Aeolian Sand Dual-Phase Medium Filling Material, Bai Zhongrong Jun 2020

Stacking Angle Of Slurry-Aeolian Sand Dual-Phase Medium Filling Material, Bai Zhongrong

Coal Geology & Exploration

Stacking angle is an important parameter to describe the spatial accumulation pattern of filling material in the goaf. It has important guiding significance for determining the drilling distance, optimizing the slurry configuration and adjusting the grouting process parameters. In order to grasp the variation law of stacking angle of slurry-aeolian sand dual-phase medium filling material, using self-flow stacking model experiment of tailings and rheological properties experiment, the mixing ratio of aeolian sand was taken as a variable to determine the slurry accumulation parameters and rheological parameters on different conditions of sand ratio. Based on this, Sofra & Boger formula was …


Regional Distribution And Geotectonic Control Of Late Permian Tectonically Deformed Coal In Zhina Coalfield, Zhou Peiming, Gao Wei, Deng Lan, Fu Wei Jun 2020

Regional Distribution And Geotectonic Control Of Late Permian Tectonically Deformed Coal In Zhina Coalfield, Zhou Peiming, Gao Wei, Deng Lan, Fu Wei

Coal Geology & Exploration

In order to find out the tectonically deformed coal distribution law of Zhina coalfield, by sorting out and analyzing the data of more than 200 coal-bearing structural units including Bide syncline, Santang syncline, Zhuzang syncline, Arcong syncline and Guanzhai syncline in Zhina coalfield, Guizhou Province, combined with logging curve analysis, the regional distribution characteristics of coal body structure and structural control factors of No.6, No.16 and No.27 main coal seams are comprehensively analyzed. The study shows that from the west to the east, the proportion of tectonically deformed coal in Zhina coalfield increases gradually. The coal in the western part …


Physical Simutation Experiment Investigation On Hydraulic Fracture Propagation In High-Dip Coal Seam, Jiang Wei, Zhang Jun, Zhong Jie, Zhao Chen, Tang Zhuyun, Lu Haibing, Yi Xinbin, Wang Hai Jun 2020

Physical Simutation Experiment Investigation On Hydraulic Fracture Propagation In High-Dip Coal Seam, Jiang Wei, Zhang Jun, Zhong Jie, Zhao Chen, Tang Zhuyun, Lu Haibing, Yi Xinbin, Wang Hai

Coal Geology & Exploration

In order to study the hydraulic fracture geometry in high-dip coal seam, a large-scale true triaxial fracturing simulation system was used to carry out physical simulation experiments, and the hydraulic fracture geometry of the maximum horizontal principal stress along the strike direction and along the dip direction-in 60° dip coal seam were investigated respectively. Experimental results of the maximum principal stress direction along the strike direction show that: hydraulic fracture initiation is easily; fracture height is limited in the whole time; fracture connectivity is good; fracture propagates mainly along bedding and natural fracture, vertical fracture is formed; the influence of …


Surface Efficient Gas Extraction Mode Based On Full Coverage Of Working Face, Fang Jiawei, Han Baoshan, Zhou Jiajia, Wang Zhengxi, Zhang Dingliang, Liu Jia, Xu Jianjun Jun 2020

Surface Efficient Gas Extraction Mode Based On Full Coverage Of Working Face, Fang Jiawei, Han Baoshan, Zhou Jiajia, Wang Zhengxi, Zhang Dingliang, Liu Jia, Xu Jianjun

Coal Geology & Exploration

Aiming at the problems of soft and broken coal seam, low permeability, difficulty in gas extraction and low drainage efficiency in working face, a full-coverage mode for gas extraction in working face through the horizontal well group with staged fracturing roof at both ends is proposed. Taking a mine in Suxian mining area of Huaibei coalfield as an example, based on the characteristics of in-situ stress and working face distribution, combined with the analysis of gas geological conditions and coal seam mechanical properties in the area, the cross section dipole sonic logging method was used to optimize the orientation of …