Experimental Study On Heat Transfer Performance Of Double U-Shaped Buried Tube Heat Exchanger,
2023
China Coal Research Institute, Beijing 100013, China; China Coal Pingshuo Group Co., Ltd., Shuozhou 036006, China
Experimental Study On Heat Transfer Performance Of Double U-Shaped Buried Tube Heat Exchanger, Li Lei, Zhang Weidong, Xu Shuanhai, Zhao Yongzhe, Dang Dongsheng, Wang Qilong, Gou Li, Lei Yanzi
Coal Geology & Exploration
Double U-shaped buried tube heat exchanger (DUBTHE) are prone to pipe crossing and thermal short-circuiting in the practical applications, resulting in the reduced heat transfer performance and directly affecting the operational efficiency of shallow geothermal heat pump system. Based on the initial line thermal average temperature, thermal conductivity theory and slope method, and taking a shallow geothermal heat pump project in Xi'an as the engineering background. Then, this study investigate the effects of initial average temperature, thermal conductivity and volumetric heat capacity of rock-soil, and tube clamp spacing on the heat transfer performance of DUBTHE through field geotechnical thermal response …
Quality Assessment Of Resistivity Monitoring Data Of Coal Mines,
2023
CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China
Quality Assessment Of Resistivity Monitoring Data Of Coal Mines, Cui Weixiong, Yuan Bo
Coal Geology & Exploration
Resistivity monitoring of coal mines is an important technical means of preventing water hazards on the roof and floor of a mining face. However, it is difficult to guarantee high-quality resistivity data monitored and collected due to the complex and extremely strong electromagnetic interference in the monitoring environment, as well as the limitations of the maximum emission current for the purpose of safe coal mining. To select and utilize highly reliable data from the massive data monitored daily, this study compared and analyzed the advantages and disadvantages of commonly used methods for quality assessment of data obtained using the DC …
Key Technology Of Automatic Loading And Unloading System For Dual-Pipe Directional Drilling Rig And Its Application In Soft–Fragmentized Coal Seam,
2023
CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China; School of Civil, Mining and Environmental Engineering, University of Wollongong, NSW 2522, Australia
Key Technology Of Automatic Loading And Unloading System For Dual-Pipe Directional Drilling Rig And Its Application In Soft–Fragmentized Coal Seam, Li Kun, Ting Ren, Yao Yafeng
Coal Geology & Exploration
To improve the automatic level and efficiency of loading and unloading of drilling rigs during the construction of dual-pipe directional drilling, an automatic loading and unloading device of dual pipe was developed to realize the fully automatic loading and unloading of drilling rigs under different working conditions and to solve the technical problems of loading and unloading the drill pipes and casing simultaneously during the dual-pipe directional drilling. Meanwhile, the device structure and control system was designed to restrict the load applied to the device during construction with the end-compliant technique. Besides, the key boundary conditions of the control program …
Effects Of Mos2 On The Matrix Performance Of Hot-Pressed Fe-Based Diamond Drill Bit,
2023
School of Civil and Architectural Engineering, Liaoning University of Technology, Jinzhou 121001, China
Effects Of Mos2 On The Matrix Performance Of Hot-Pressed Fe-Based Diamond Drill Bit, Zhang Wenjiao, Tan Songcheng, Pan Bingsuo, Jin Xin, Kong Xiangqing, Long Shanglin
Coal Geology & Exploration
Diamond drill bit is a common rock breaking tool in various exploration works, but the diamond in drill bit has poor thermal stability. As heat is constantly generated during the drilling process, the self-cooling of diamond drill bit under the condition of drought and water shortage is very important to improve the drilling efficiency. In order to decrease the friction coefficient between bit matrix and rock interface under dry drilling condition and reduce the thermal damage of diamond during drilling, molybdenum disulfide (MoS2) was added into the Fe-based diamond bit matrix, and research was performed for the effects …
Study On Construction Of Microbial Solid-Free Drilling Fluid System And Its Borehole Wall Enhancement Mechanism,
2023
State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China; College of Environment and Civil Engineering, Chengdu University of Technology, Chengdu 610059, China
Study On Construction Of Microbial Solid-Free Drilling Fluid System And Its Borehole Wall Enhancement Mechanism, Li Zhijun, Zhu Mao, Zhi Jingzi, Han Yi, Chen Junxiu, Zhao Gan
Coal Geology & Exploration
Broken formations are often encountered during drilling, which is prone to the instability of wellbore wall and induces serious downhole accidents. Enhancing the cementing force between the broken blocks and improving the mechanical strength of the surrounding rocks of a wellbore is one of the effective ways to solve the instability of wellbore in this type of formation, for which the microbially induced calcite precipitation (MICP) technology provides a good reference. To this end, the growth of Bacillus pasteurii in the solid-free drilling fluid system was analyzed through experimental study, and thus a solid-free drilling fluid suitable for its growth …
Table Of Contents,
2023
China Coal Technology and Engineering Group (CCTEG)
Effect Of Amf-Maize Combination On Water And Salt Distribution In Soil Under The Dump Reconstruction Mode Of “Topsoil-Aquifer-Aquitard”,
2023
Institute of Ecological Environment Restoration in Mine Areas of West China, Xi’an University of Science and Technology, Xi’an 710054, China; College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054, China; State Key Laboratory for Coal Resources and Safe Mining, China University of Mining and Technology (Beijing), Beijing 100083, China
Effect Of Amf-Maize Combination On Water And Salt Distribution In Soil Under The Dump Reconstruction Mode Of “Topsoil-Aquifer-Aquitard”, Bi Yinli, Yang Wei, Ke Zengming, Wu Chao, Li Mingchao, Xue Chao
Coal Geology & Exploration
The distribution of soil water and salt severely affects the ecological reconstruction and plant configuration modes at coal mine dumps. To investigate the characteristics of soil water and salt distribution under the three-layer reconstruction mode of “topsoil-aquifer-aquitard” in coal mine dump under the influence of mycorrhizal plants, laboratory soil column test was conducted, in which the soil was treated in three ways: planting maize and inoculating with arbuscular mycorrhizal fungi (YM+AMF), planting maize (YM) only, and no planting of maize + no inoculation with bacteria (CK). The results showed that: (1) The different treatments have no significant effect on the …
Effects Of Actinomycetes On Root Growth Of Onobrychis Viciaefolia And Rhizosphere Soil Fertility In Dumping Site Of Open-Pit Mine In Arid Area,
2023
Key Laboratory of Northwest Water Resource, Environment and Ecology (Ministry of Education), Xi’an University of Architecture and Technology, Xi’an 710054, China
Effects Of Actinomycetes On Root Growth Of Onobrychis Viciaefolia And Rhizosphere Soil Fertility In Dumping Site Of Open-Pit Mine In Arid Area, Cao Shumiao, Wang Qiangmin, Yang Fan, Yang Jian, Zhang Haihan, Xu Ganggang, Zhu Shibin
Coal Geology & Exploration
In order to resolve the issue of soil degradation in the dumping site of open-pit coal mine in arid area, the effects of actinomycetes on the root growth and rhizosphere soil fertility of onobrychis viciaefolia in the dumping site of Xinjiang Heishan Open-pit Coal Mine were investigated by highly efficient actinomycete inoculation and in-situ pot experiment. The results show that: (1) Under the drought conditions, actinomycetes inoculation could significantly promote the development of root morphology and the growth of onobrychis viciaefolia. Compared with the control without actinomycetes inoculation, the total root length, average root diameter, root surface area and …
Progress And Reflection Of Intelligent Geological Guarantee Technology In Coal Mining Face,
2023
China Coal Technology & Engineering Group Co., Ltd., Beijing 100013, China
Progress And Reflection Of Intelligent Geological Guarantee Technology In Coal Mining Face, Wang Guofa, Zhang Jianzhong, Xue Guohua, Liu Zaibin, Liu Qing, Li Mei, Liu Junfeng, Cheng Jian, Zhang Xueliang
Coal Geology & Exploration
Coal mine geological guarantee technology is the key path to achieve accurate and green coal mining. In view of the requirements of intelligent mining and geological guarantee, the main problems faced by the geological guarantee of the mining face were analyzed, mainly including the weak basic theoretical research, insufficient geological exploration accuracy, modeling accuracy unable to meet the engineering application, difficulties in model dynamic updating, and lack of optimal decision-making means for global path of intelligent mining based on spatio-temporal evolution. According to the faced difficulties and technical status, the author explored and practiced the geological guarantee technology of intelligent …
Electromagnetic Methods In The Detection Of Water Hazards In Coal Mines: A Review,
2023
College of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, China
Electromagnetic Methods In The Detection Of Water Hazards In Coal Mines: A Review, Zhang Jifeng, Sun Naiquan, Liu Zuiliang, Qi Zhipeng
Coal Geology & Exploration
Water hazards in coal mines are a major type of hidden danger in safe coal mining. The accurate detection of hidden factors to cause hazard is the prerequisite to solving the water hazards. Electromagnetic methods, which are sensitive to low-resistivity bodies and have multiple types and high adaptability, can be used to effectively detect water-rich hazard-causing factors. Traditional ground electromagnetic methods, including the controlled source audio-frequency magnetotellurics (CSAMT) method and the loop source transient electromagnetic method, play an important role in detecting hidden hazard-causing factors in coal mines. With the continuous development of new technologies, near-source electromagnetic methods have developed …
A Review On Research Of Reflected In-Seam Wave Detection Technology In Coal Mine,
2023
CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China
A Review On Research Of Reflected In-Seam Wave Detection Technology In Coal Mine, Wang Ji, Ye Hongxing, Zhang Guangzhong, Li Gang, Wu Guoqing, Niu Huan, Yang Yanjun, Guan Qi
Coal Geology & Exploration
Reflected in-seam wave can be used in one roadway to detect the abnormal geological structures such as faults in some area on both sides of the roadway or in front of tunneling. In this paper, the data and processing method of the reflected in-seam wave were compared based on the 2 different detection areas on side of the roadway and in front of tunneling. In particular, the technical principles, applicable conditions and research progress of three imaging methods of reflected in-seam wave were analyzed and sorted out, including the stack imaging, migration imaging and advance imaging of tunneling face. Besides, …
Detection Of Change In The Coal Thickness Of A Fully Mechanized Mining Face Based On Electromagnetic Wave Penetration,
2023
Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining (Anhui University of Science and Technology), Huainan 232001, China; School of Earth and Environment, Anhui University of Science and Technology, Huainan 232001, China
Detection Of Change In The Coal Thickness Of A Fully Mechanized Mining Face Based On Electromagnetic Wave Penetration, Wu Rongxin, Li Xiang, Xiao Yulin
Coal Geology & Exploration
A fully mechanized mining face tend to show great change in coal thickness, which affects the safe, efficient coal mining. Therefore, it is necessary to detect the change in the coal thickness before stoping. To determine the response of electromagnetic (EM) wave penetration to the change in the coal thickness, this study established a three-dimensional model of fully mechanized mining faces using simulation software. On this basis, this study simulated the change in the coal thickness under different ratios of the coal-to-rock resistivity based on EM wave penetration. The results are as follows: (1) With a decrease in the coal …
Development Status And Trend Of High-Density 3d Seismic Exploration Technology For Coal Fields,
2023
School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China
Development Status And Trend Of High-Density 3d Seismic Exploration Technology For Coal Fields, Dong Shouhua, Huang Yaping, Jin Xueliang, Yang Guangming, Nie Ailan, Qi Xuemei, Cheng Yan, Wu Haibo
Coal Geology & Exploration
Traditional 3D seismic exploration in coal mining areas is difficult to meet the requirements of transparent and accurate geological exploration for safe and efficient coal mining due to its low precision for complex structures, lower coal seams, and limestones. In this case, high-density 3D seismic exploration technology for coal fields emerged. This technology has undergone three developmental stages in China, namely the exploration and test stage during 2005‒2007, the test and demonstration stage during 2008‒2014, and the promotion and application stage since 2015. After nearly 20 years of development, its accuracy for the exploration of complex geological structures has been …
Source And Release Law Of Fluorine In Water-Rock System Of Coal Mine Goaf In Contiguous Area Of Shaanxi And Inner Mongolia,
2023
CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China; Shaanxi Engineering Research Center of Mine Ecological Environment Protection and Restoration in the Middle of Yellow River Basin, Xi’an 710077, China
Source And Release Law Of Fluorine In Water-Rock System Of Coal Mine Goaf In Contiguous Area Of Shaanxi And Inner Mongolia, Wang Tiantian, Jin Dewu, Xue Jiankun, Ji Hongying, Shang Hongbo, Zhou Zhenfang, Yang Jian, Cao Yu
Coal Geology & Exploration
The coal mine goaf is the key area for the formation of high-fluoride mine water, and the source and release of fluorine in goaf water-rock system determines the enrichment or depletion of fluorine in mine water. Aiming at the unclear source and release rule of fluorine in the mine water of 3-1 coal goaf in the contiguous area of Shaaxi and Inner Mongolia, hydrochemical test, mineral composition analysis, mineral scanning electron microscopy and energy spectrum detection, as well as laboratory water-rock simulation experiment, were conducted to determine the source and occurrence carrier of fluorine in coal mine water, and to …
A Preliminary Study On The Multiscale Effect Of Seismic Anisotropy Of Coal Seams At Long Wavelengths,
2023
Multi-Wave & Multi-Component (MWMC) Research Group, School of Geophysics and Information Technology, China University of Geosciences (Beijing), Beijing 100083, China
A Preliminary Study On The Multiscale Effect Of Seismic Anisotropy Of Coal Seams At Long Wavelengths, Wang Yun, Zheng Yongqin, Yang Chun, Zhang Yi, Li Yingda, Zhang Huimin
Coal Geology & Exploration
Terrestrial coal-bearing strata in China are all typical thin interbeds given the seismic frequency bands of coal exploration. The isotropic thin interbeds are superimposed in the coal-bearing strata, exhibiting seismic anisotropy at long wavelengths among different seismic wavelengths, for which simplified equivalent processing, such as vertical transverse isotropy (VTI) or isotropy (ISO) approximation, is generally adopted in seismic exploration. However, the long-wave approximation has different applicable conditions for strata with different elastic properties. Taking the coal-bearing strata in the Huainan Coalfield as an example, this study established two-dimensional models of horizontal thin interbeds using acoustic and density logging curves of …
Preparation And Characteristics Of Inorganic Curing Foam With Large-Volume Fly Ash In Goaf,
2023
College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
Preparation And Characteristics Of Inorganic Curing Foam With Large-Volume Fly Ash In Goaf, Ma Li, Du Su, Zhang Zhaoyun, Wang Hui, Zhao Liang, Zhang Bo
Coal Geology & Exploration
Air leakage in the goaf of coal mine is an important cause of coal fire disaster. The traditional filling and plugging materials are easy to crack, with poor fluidity and high cost. Therefore, it is necessary to develop new materials for effective filling and plugging of the air leakage channels. Herein, the new filling and plugging material of inorganic curing foam with large-volume fly ash was developed by optimizing the mix ratio based on material fluidity, initial setting time and compressive strength using the single factor variable method. Meanwhile, the material hydration process was characterized by the infrared spectroscopy, X-ray …
Technological Path And Geological Guarantee For Energy Storage In Underground Space Formed By Coal Mining,
2023
College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054, China; Key Laboratory of Coal Resources Exploration and Comprehensive Utilization, Ministry of Natural Resources, Xi’an 710021, China
Technological Path And Geological Guarantee For Energy Storage In Underground Space Formed By Coal Mining, Sun Qiang, Zhang Weiqiang, Geng Jishi, Hu Jianjun, Zhang Yuliang, Lyu Chao, Ge Zhenlong, Li Pengfei, Jia Hailiang, Liu Yabin, Li Yuxiang
Coal Geology & Exploration
Coal resource is still in the main position of China’s energy structure, but the development of coal industry is facing the new challenge of “carbon peaking and carbon neutrality”. Actively developing coal underground space energy storage technology is an effective means to promote low-carbon and clean energy utilization, and also a key measure to ensure China’s energy strategic security. This study discussed the potential utilization of underground space formed by coal mining based on the current energy storage technologies. Focusing on new energy storage technologies such as underground pumped storage hydropower plants in coal mines (UPSHCM), thermal energy storage (TES), …
Experimen On Mechanical Properties Of Various Graded Collapse Column Fills,
2023
State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, China; College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Experimen On Mechanical Properties Of Various Graded Collapse Column Fills, Liu Weitao, Du Yanhui, Pang Lifu, Meng Xiangxi, Shen Jianjun, Hu Yingying
Coal Geology & Exploration
In order to study the mechanical properties of collapse column fill under different consolidation pressures and grain compositions. Base on similar simulated rock-soil mass sample under different states of geotechinal consolidation test preparing, we investigated the mechanical characteristics and microstructure evolution mechanism of collapse column filling by conducting the triaxial loading test, mercury intrusion porosimetry and scanning electron microscopy in different states of rock-soil mass. The results show that the rock-soil mass has obvious shaping characteristics and the stress-strain curve can be divided into four stages: pore compaction stage, stable deformation stage, deformation failure stage and creep-like stage. The compressive …
Evaluation On Spatiaotemporal Variations Of Mine Water Quality And Water Source Identification Based On Key Dominant Factors In Loess Hilly And Gully Region,
2023
College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Evaluation On Spatiaotemporal Variations Of Mine Water Quality And Water Source Identification Based On Key Dominant Factors In Loess Hilly And Gully Region, Shi Longqing, Qu Xingyue, Han Jin
Coal Geology & Exploration
It is difficult to accurately identify the sources of water inrush between sandstone-mudstone interbedded overburden in loess hilly and gully region, and these proportions of different water sources cannot be quantified. For this reason. Based on the systematic collection of surface water and groundwater samples from Zhujiamao Coal Mine in northern Shaanxi. This study revealed the hydrochemical evolution laws of water quality and the recharge relationship of various aquifer systems by mathematical statistics, Piper (trilinear) diagram, Gibbs diagram and the conventional hydrochemical characteristic method. Meanwhile, this study analyzed the evolution characteristics of stable isotopic composition in water, clarified the spatial …
Progress Of Research On Key Technologies For Hydrogeochemical Prospecting In North China Type Coalfield,
2023
School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009, China
Progress Of Research On Key Technologies For Hydrogeochemical Prospecting In North China Type Coalfield, Chen Luwang, Hu Yongsheng, Zhang Jie, Zhang Miao, Zheng Jian, Zheng Xin, Zhang Yuanyuan, Cai Xinyue, Wu Minghui
Coal Geology & Exploration
North China type coalfield is an important coal base in China, and hydrogeochemical prospecting is an important means to solve a series of hydrogeological problems in the process of coal mining. The typical hydrogeological problems under the influence of mining were analyzed based on the generalization of the typical hydrogeological structure of North China type coalfield. Meanwhile, the multi-field coupling relationship of groundwater and the mechanism of hydrogeochemical prospecting in North China type coalfield, as well as its testing, analysis and treatment technology, were revealed. Besides, the reliability of hydrogeochemical prospecting technology in North China type coalfield was pointed out …
