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Full-Text Articles in Engineering

A New Model Of Surface And Underground Integrated Three-Dimensional Prevention And Control Of Rock Burst In Binchang Mining Area, Wu Xueming, Ma Xiaohui, Lyu Dazhao, Zheng Kaige, Wang Dongjie Mar 2023

A New Model Of Surface And Underground Integrated Three-Dimensional Prevention And Control Of Rock Burst In Binchang Mining Area, Wu Xueming, Ma Xiaohui, Lyu Dazhao, Zheng Kaige, Wang Dongjie

Coal Geology & Exploration

With the continuous increase of coal mining intensity, the mine gradually moves to the deep, bringing about increasingly serious rock burst hazard. The deep rock burst mines often have one or more layers of hard and thick rock strata. These hard roofs are thick and strong integrity. When they suddenly rupture, they can release a large amount of elastic energies, which can easily to cause rock burst accidents and seriously restrict the safety of mine production. Herein, appropriate treatment measures were put forward for the special situation of deep burial depth of coal seam and general presence of many kinds …


Co2-Ecbm Simulation Study Considering Klinkenberg Factor State, Sa Zhanyou, Wu Jingbo, Yang Yongliang, Zhang Xin, Lu Shouqing, Liu Jie, Wang Hao Mar 2023

Co2-Ecbm Simulation Study Considering Klinkenberg Factor State, Sa Zhanyou, Wu Jingbo, Yang Yongliang, Zhang Xin, Lu Shouqing, Liu Jie, Wang Hao

Coal Geology & Exploration

In order to explore the role of Klinkenberg effect and Klinkenberg factor in different states in the process of CO2-Enhanced Coal Bed Methane (CO2-ECBM), the effects of Klinkenberg factor of zero, fixed Klinkenberg factor and dynamic Klinkenberg factor on CO2-ECBM were simulated and analyzed by COMSOL finite element software. The dynamic changes of CH4 and CO2 pressure with this factor were studied, and the CH4 gas production was compared with the engineering practice. The results show that the effective permeability of CH4 and CO2 increases slowly at first, then …


Ecological Environment Assessment Of Shanxi Province And Planned Mining Area Based On Coupling Remote Sensing Ecological Index (Rsei) Model, Ji Xianglin, Yan Yueguan, Guo Wei, Teng Yongjia, Zhao Chuanwu Mar 2023

Ecological Environment Assessment Of Shanxi Province And Planned Mining Area Based On Coupling Remote Sensing Ecological Index (Rsei) Model, Ji Xianglin, Yan Yueguan, Guo Wei, Teng Yongjia, Zhao Chuanwu

Coal Geology & Exploration

Ecological environment quality is an important indicator to evaluate the livability, and quantitative assessment on the change rule of regional ecological environment quality could provide scientific basis for the regional ecological environment protection and governance. Taking Shanxi Province and its planned mining area as the research area, the original Remote Sensing Ecology Index (RSEI) is added with Net Primary Productivity (NPP) and Habitat Quality (HQ) to characterize the carbon sink level and habitat suitability respectively based on Google Earth Engine (GEE) platform. Herein, three representative years from 2000 to 2018 were selected for analysis. Specifically, the temporal and spatial heterogeneity …


Influencing Mechanism Of Rock Thermal Resistance On Convective Heat Transfer Of Fracture, Wang Yaning, Lu Chuan, Wang Guiling Mar 2023

Influencing Mechanism Of Rock Thermal Resistance On Convective Heat Transfer Of Fracture, Wang Yaning, Lu Chuan, Wang Guiling

Coal Geology & Exploration

The convective heat transfer characteristics between high temperature rocks and fluids in Enhanced Geothermal Systems (EGS) have been an important fundamental element of research on Hot Dry Rock (HDR). The thermal resistance of rock has an important influence on the convective heat transfer characteristics of fracture. In order to study its specific influence, two research methods, i.e., the theoretical analysis and the numerical simulation, were used in combination to study the heat transfer law between two parallel smooth flat plates by discussing the analytical solution and establishing the numerical model. The results show that the local Nusselt number Nux …


Development Of Storage Equipment Of Continuous Cable Pipe For Borehole Rescue, Gao Ke, Niu Xin, Zhao Yan, Qin Xiaolin, Lyu Xiaoshu, Xie Xiaobo Mar 2023

Development Of Storage Equipment Of Continuous Cable Pipe For Borehole Rescue, Gao Ke, Niu Xin, Zhao Yan, Qin Xiaolin, Lyu Xiaoshu, Xie Xiaobo

Coal Geology & Exploration

The double-bit bionic self-balancing continuous drilling technology has the advantages including requiring no drilling rig, high drilling speed and slight disturbance to the borehole wall. It is one of the key potential technologies for constructing the security and rescue passages against mine disasters. In this technology, as there are passages for power supply, signal, chip removal and other aspects that are built in the continuous cable pipe, it is required that there shall be no such interference, extrusion or arrangement of dynamic/static conductive electric conduction link as in using the existing drum hoist to store continuous pipes during storage. Therefore, …


Research On Control System Of Drill Pipe Conveying Device Based On Fuzzy Particle Swarm Optimization, Zhang Ning, Liu Qi, Shao Junjie, Chang Jianghua, Luo Pengping, Zou Zujie Mar 2023

Research On Control System Of Drill Pipe Conveying Device Based On Fuzzy Particle Swarm Optimization, Zhang Ning, Liu Qi, Shao Junjie, Chang Jianghua, Luo Pengping, Zou Zujie

Coal Geology & Exploration

In the tripping operation of large-diameter rescue well construction, the drill pipe conveying device used for large-diameter drilling tool transportation and drill string connection. In view of the problem that it is difficult to quickly and accurately lift the drill pipe to the angle of power head for make-up due to its easy vibration in the process of positioning, the structural characteristics and working principle of the drill pipe conveying device were analyzed at first. The kinematic model for the lifting of drill pipe was deduced with the structural relationship, obtaining the mapping relationship in the motion law of the …


Experimental Study On Effect Of Soil Layer Reconstruction And Inoculation On Plant Root Hydraulic Lift In Open-Pit Coal Mine Dump, Bi Yinli, Gao Xuejiang, Ke Zengming, Xiao Li Dec 2022

Experimental Study On Effect Of Soil Layer Reconstruction And Inoculation On Plant Root Hydraulic Lift In Open-Pit Coal Mine Dump, Bi Yinli, Gao Xuejiang, Ke Zengming, Xiao Li

Coal Geology & Exploration

Soil layer reconstruction of open-pit coal mine dump is of great significance for ecological reconstruction. In order to study the effect of inoculation of dark septate endophytes (DSE) on water utilization of corn root system under different reconstructed soil layer models, soil column simulating and culturing test was adopted, with DSE inoculation and control treatment set up under each of the four soil layer types, in a total of 8 groups. The results show that the roots of corn are the longest with the maximum density under the treatment with 20% loess, which are 3.2, 2.4 and 2.8 times that …


Effect Of Coal Mining Subsidence Fractures On Source Of Water Absorption Of Artemisia Desertorum, Shang Jingxuan, Chen Shi, Liu Qianwen, Guo Xufeng, Guo Junting, Li Mi Dec 2022

Effect Of Coal Mining Subsidence Fractures On Source Of Water Absorption Of Artemisia Desertorum, Shang Jingxuan, Chen Shi, Liu Qianwen, Guo Xufeng, Guo Junting, Li Mi

Coal Geology & Exploration

Ground fissures caused by coal mining subsidence are not only a serious geological hazard, but also affect the growth and development of vegetation in the mining area and damage the mining ecosystem. To investigate the quantitative influence of coal mining subsidence fractures on the source of water uptaken by Artemisia Desertorum, the simulated precipitation tests of isotopically-labeled water were conducted in three test areas influenced by coal mining subsidence fractures to different degrees on 22312-working face of Huojitu mine field in Shendong mining area. The three test areas were divided according to the distance between Artemisia Desertorum and the fractures, …


Prediction Method And Application Of Gas Emission From Mining Workface Based On Stl-Eemd-Ga-Svr, Lin Haifei, Liu Shihao, Zhou Jie, Xu Peiyun, Shuang Haiqing Dec 2022

Prediction Method And Application Of Gas Emission From Mining Workface Based On Stl-Eemd-Ga-Svr, Lin Haifei, Liu Shihao, Zhou Jie, Xu Peiyun, Shuang Haiqing

Coal Geology & Exploration

Accurate prediction of gas emission can provide important basis for mine ventilation and the prevention and measures of gas disasters. In order to improve the prediction accuracy of gas emission in the mining workface, the monitoring data of gas emission were decomposed into the trend term, periodic term and irregular fluctuation term by the Seasonal-Trend decomposition procedure based on Loess (STL) based on the monitoring data of gas emission from the mining workface of Huangling Mine in Shaanxi. Besides, the irregular fluctuation term was further broken down into the Intrinsic Mode Functions (IMFs) components with different characteristics and the residual …


Evolution Law Of Water Inflow In Full Life Cycle Of Working Face In Deep Buried Inner Mongolia-Shaanxi Mining Area, Liu Yang, Yang Jian, Zhou Jianjun Dec 2022

Evolution Law Of Water Inflow In Full Life Cycle Of Working Face In Deep Buried Inner Mongolia-Shaanxi Mining Area, Liu Yang, Yang Jian, Zhou Jianjun

Coal Geology & Exploration

The deep buried Inner Mongolia-Shaanxi mining area was newly developed, where the hydrogeological characteristics under the disturbance of coal mining were still unclear. Various types of water damage problems had occurred in the process of infrastructure construction and production. Among them, no research was conducted for the variation characteristics of water inflow during and after mining in working face, which increased the difficulty in the arrangement of underground water drainage system and the work of water prevention and control. In order to find out the evolution law of water inflow in the full life cycle of working face before and …


Study On Performance Optimization Of Gasification Slag Based Paste Filling Materials In Ningdong Mining Area, Chen Denghong, Li Chao, Zhang Zhiguo Dec 2022

Study On Performance Optimization Of Gasification Slag Based Paste Filling Materials In Ningdong Mining Area, Chen Denghong, Li Chao, Zhang Zhiguo

Coal Geology & Exploration

As one of the nine coal bases at hundred million ton level in Yellow River Basin, Ningdong Mining Area has nearly 2×108 t of coal-based solid waste produced annually, and faces to the problems of large stock of gasification slag, difficulty in scaled utilization, and limited space for simple landfill. Filling mining could solve the problem of stockpiling, of which the cost is high and the performance needs to be optimized. According to the response surface method, 17 groups of central composite experiments were designed for the three factors at three levels: the mixing amount of gasification slag in …


Comprehensive Recycling Utilization Technology Of Foundation Engineering Slurry, Xie Hui, Ye Jingliang, Chen Juan, Xue Man, Hu Huicong, Yang Xianyu, Cai Jihua Dec 2022

Comprehensive Recycling Utilization Technology Of Foundation Engineering Slurry, Xie Hui, Ye Jingliang, Chen Juan, Xue Man, Hu Huicong, Yang Xianyu, Cai Jihua

Coal Geology & Exploration

Foundation engineering slurry in the fields of underground continuous walls, horizontal directional drilling, shield, and pipe jacking has the characteristics of large amount of consumption and relatively single pollutant. With the implementation of various national environmental protection laws and regulations, the comprehensive treatment of slurries is particularly important. In this paper, a set of comprehensive recycling utilization technology of foundation engineering slurry was proposed. The technology of sand removal plus recycling of purified slurry and drilling cuttings can be adopted to the circulating slurry, and the technology of calcium removing, pH reducing, flocculation separation, pressure filtration and recycling of wastewater …


Geochemical Characteristics And Sedimentary Model Of Shales In Lower Member Of Zhongjiangou Formation In Wudun Sag, Dunhuang Basin, Deng Wei, Yang Tao, Fan Shenglong, Liu Zirui, Wan Xuhui, Xiao Juanyi, Cao Taotao Dec 2022

Geochemical Characteristics And Sedimentary Model Of Shales In Lower Member Of Zhongjiangou Formation In Wudun Sag, Dunhuang Basin, Deng Wei, Yang Tao, Fan Shenglong, Liu Zirui, Wan Xuhui, Xiao Juanyi, Cao Taotao

Coal Geology & Exploration

Analysis on the sedimentary environment of shale is of great significance for the evaluation of shale gas reservoir and the optimization of sweet spot. In order to deeply explore the depositional environment of organic-rich shale and the mechanism of organic matter accumulation in the Lower member of Zhongjiangou Formation of Wudun Sag in Dunhuang Basin, the TOC content, maceral composition, carbon isotope, major elements, trace elements and rare earth element were tested based on DY1 well. The results indicate that the lithologies of the Lower member of Zhongjiangou Formation in Wudun Sag are gray-black carbonaceous shale and silty shale with …


Experimental Study On High-Pressure Hydraulic Percussive Rotary Drilling Based On Single-Tooth Rock-Breaking Process, Dou Xuqian, Yao Ningping, Li Xiushan, Wang Li, Zhang Kai, Wei Hongchao Dec 2022

Experimental Study On High-Pressure Hydraulic Percussive Rotary Drilling Based On Single-Tooth Rock-Breaking Process, Dou Xuqian, Yao Ningping, Li Xiushan, Wang Li, Zhang Kai, Wei Hongchao

Coal Geology & Exploration

Aiming at the problem of low efficiency of hard rock drilling in crossing borehole in underground coal mine, the morphology of crushing pit formed by column tooth under the percussive load was analyzed based on the percussive rotary drilling mechanism and the main characteristics of Wassara high-pressure hydraulic impactor, and the crushing pit was divided into the four areas of disintegration area, compact area, crack area and elastic area. On this basis, process analysis was performed on the continuous tooth rock-breaking with large and small interval impact. Meanwhile, the technical parameters of high-pressure hydraulic percussive rotary drilling were discussed with …


Precise Magnetotelluric Single-Component Processing Technology And Detection Of Deep Disaster-Causing Water Body, Li Peitao, Wu Qiang, Li Zhuorong, Li Wenyu, Xie Jian, Wang Yuxi Dec 2022

Precise Magnetotelluric Single-Component Processing Technology And Detection Of Deep Disaster-Causing Water Body, Li Peitao, Wu Qiang, Li Zhuorong, Li Wenyu, Xie Jian, Wang Yuxi

Coal Geology & Exploration

In order to realize the fine detection of hydrogeological conditions by natural source single-component magnetotelluric technology, the problems of magnetotelluric signal acquisition and processing were systematically analyzed, and study was conducted for the response characteristics of underground water-rich area on magnetotelluric wave. Besides, water-richness index model was established according to the magnetotelluric sounding theory and analytic hierarchy process. Moreover, the corresponding relationship between waveform and lithology was fitted based on a large amount of experimental data, and the information on physical properties, such as the dielectric constant, elastic brittleness, density and porosity was extracted from the fractal dimension of waveform. …


Table Of Contents, The Editors Dec 2022

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Laws And Prevention Methods Of Ground Cracks In Shallow Coal Seam Mining, Hou Enke, Xie Xiaoshen, Feng Dong, Chen Qiuji, Che Xiaoyang, Hou Pengfei Dec 2022

Laws And Prevention Methods Of Ground Cracks In Shallow Coal Seam Mining, Hou Enke, Xie Xiaoshen, Feng Dong, Chen Qiuji, Che Xiaoyang, Hou Pengfei

Coal Geology & Exploration

The large-scale and high-intensity mining of shallow coal seams in northern Shaanxi has induced serious ground collapse, resulting in land damage in large area, water and soil loss, and vegetation death, and thus leading to the epigenetic environment degradation. In order to understand the development law of ground collapse and fracture in shallow coal seam mining, clarify its mechanism, and put forward the appropriate treatment and restoration measures to realize the coordinated development of “coal-water-ecology”, Zhangjiamao mine field and Ningtiaota mine field in northern Shaanxi were taken as the study area. On this basis, the development law and control methods …


Influence Of Thick Sandstone On Development Of Overburden Mining Fissures In Northern Shaanxi Coal Mining Area Of Yellow River Basin And Suggestions On Water-Preserved Coal Mining, Wang Shuangming, Wei Jiangbo, Song Shijie, Wang Shengquan, Sun Tao Dec 2022

Influence Of Thick Sandstone On Development Of Overburden Mining Fissures In Northern Shaanxi Coal Mining Area Of Yellow River Basin And Suggestions On Water-Preserved Coal Mining, Wang Shuangming, Wei Jiangbo, Song Shijie, Wang Shengquan, Sun Tao

Coal Geology & Exploration

The change of geological conditions of coal seam roof overburden and the development of mining fissures caused by coal mining activities are the direct causes of damage to the key underground aquifers, and also the root causes of ecological environment degradation in the mining area. As a typical geological condition, the thick sandstone developed in the overburden structure of the coal seam roof has an important impact on the development law of mining fissures in the overburden. Therefore, the influence of the thickness and location of different thick sandstones on the development morphology and height of overburden mining fractures was …


Geological Soil Formation For Ecological Restoration Of Mining Areas And Its Case Study, Hu Zhenqi, Zhang Zixuan, Sun Huang Dec 2022

Geological Soil Formation For Ecological Restoration Of Mining Areas And Its Case Study, Hu Zhenqi, Zhang Zixuan, Sun Huang

Coal Geology & Exploration

Soil is an important substrate of plant growth, as well as the key for successful ecological restoration of mine. In view of the status of insufficient soil for most of ecological restoration of mine and the reality of a very long process of geological soil formation, the concept and method of geological soil formation for ecological restoration of mine (Mine-GSF for short) were discussed on the basis of description on the principle of natural geological soil formation. Natural geologic soil formation is the process of turning “rock” into “soil” through a long period of macro-geological cycle and biological cycle, including …


Succession Process And Management Mode Of Land Reclamation In Open-Pit Coal Mine Areas Based On Vegetation Rehabilitation, Zhou Wei, Guan Yanjun Dec 2022

Succession Process And Management Mode Of Land Reclamation In Open-Pit Coal Mine Areas Based On Vegetation Rehabilitation, Zhou Wei, Guan Yanjun

Coal Geology & Exploration

Rehabilitated vegetation plays an important role in energy exchange and ecological cycling, and its dynamic change can characterize the extensive details of the disturbance to and the restoration of ecosystem in coal mining areas. From the points of different disturbance states of vegetation in the coal mining area, such as the undisturbed state, the coal mining disturbance state, the restoration state and the post-restoration state, six succession scenarios of the rehabilitated vegetation in coal mining areas were analyzed, including the effective restoration to maturity, inefficient restoration to maturity, effective restoration followed by degradation, effective restoration to development, inefficient restoration to …


Evaluation On Potential Of Using Abandoned Mines For Pumped Storage In Nine Provinces Of Yellow River Basin, Bian Zhengfu, Zhu Chaobin, Zhou Yuejin, Xu Yunong Dec 2022

Evaluation On Potential Of Using Abandoned Mines For Pumped Storage In Nine Provinces Of Yellow River Basin, Bian Zhengfu, Zhu Chaobin, Zhou Yuejin, Xu Yunong

Coal Geology & Exploration

In view of the low utilization rate of closed mine resources and the increasing demand for power and energy storage in China, the pumped storage technology of abandoned mine is an effective means to realize the secondary development and utilization of resources and enhance the peak sheaving capacity of power grid. Based on the working principle and development status of pumped storage power plants using the abandoned mines, it was proposed to build the semi-underground and full-underground pumped storage power plants using the abandoned mines in the nine provinces of Yellow River Basin. By considering the influence factors of space, …


Preparation Of Coal-Series Solid-Waste-Based Green Filling Materials And Their Performance, Dong Meng, Li Jiangshan, Chen Xin, Jin Jiaxu, Lu Longzhao Dec 2022

Preparation Of Coal-Series Solid-Waste-Based Green Filling Materials And Their Performance, Dong Meng, Li Jiangshan, Chen Xin, Jin Jiaxu, Lu Longzhao

Coal Geology & Exploration

The filling technology is an important part of green mining. The low-carbon environmental-friendly filling materials with low costs in research and development and reliable performance are critical for the development of filling technologies. The coal gangue (CG) and coal-series metakaolin (MK) were adopted as the raw materials to prepare coal-series solid-waste-base green filling materials, and the effect of the mixing proportion and alkali activator on the strength and fluidity of filling materials was discussed. In combination with the X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric (TG) analysis and scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM-EDS) and other characterization measures, …


Shear Characteristics And Modified Coulomb Model Of Alfalfa Root-Loess Composite, Duan Zhao, Yuan Lin, Bi Yinli, Wang Kai, Wu Yanbin, Zhang Qing Dec 2022

Shear Characteristics And Modified Coulomb Model Of Alfalfa Root-Loess Composite, Duan Zhao, Yuan Lin, Bi Yinli, Wang Kai, Wu Yanbin, Zhang Qing

Coal Geology & Exploration

Plant roots can significantly improve the strength of soil. In order to explore the enhancement effect of alfalfa root on the shear strength of loess, study was conducted based on the root-soil composites of alfalfa with a growth period of 60 d herein. Specifically, the parameters on shear strength of the alfalfa root-soil composite and the tensile strength of alfalfa root were obtained through the direct shear tests and root tensile tests. By observing the structure and characteristics of alfalfa root with an electronic magnifier, a modified Coulomb model of root-soil composite was established with the empirical formula. Meanwhile, the …


Discussion On Identification Standard Of Coal-Measure Graphite, Cao Daiyong, Wang Lu, Zhu Wenqing, Wu Guoqiang, Wei Yingchun, Ning Shuzheng, Wang Guixiang, Xiao Jincheng, Xu Xiang, Liu Kang Dec 2022

Discussion On Identification Standard Of Coal-Measure Graphite, Cao Daiyong, Wang Lu, Zhu Wenqing, Wu Guoqiang, Wei Yingchun, Ning Shuzheng, Wang Guixiang, Xiao Jincheng, Xu Xiang, Liu Kang

Coal Geology & Exploration

The identification and classification of coal-measure graphite are the precondition and basic work of mineral geological exploration, as well as resource exploitation and utilization. The preparation of identification standards of coal-measure graphite should follow the principles of science, systematicness, applicability and operability. Coal graphitization and coalification is a continuous progression plus jump process, and the characteristics of coal-measure graphite, including the step evolution of macromolecular structure and the heterogeneity of material composition, leads to the complexity of ore identification. In order to establish the scientific and practical identification standards, and from the study of metallogenic mechanism and the demand of …


Experimental Research On Mechanical Properties Of “Jacked Pipe-Frozen Soil” Composite Structure In Freeze-Sealing Pipe Roof Tunnel, Duan Yin, Rong Chuanxin, Cai Haibing, Long Wei Dec 2022

Experimental Research On Mechanical Properties Of “Jacked Pipe-Frozen Soil” Composite Structure In Freeze-Sealing Pipe Roof Tunnel, Duan Yin, Rong Chuanxin, Cai Haibing, Long Wei

Coal Geology & Exploration

As the key project of Zhuhai Connecting Line of Hong Kong‒Zhuhai‒Macao Bridge, the underground excavation section of Gongbei Tunnel has applied the freeze-sealing pipe roof method for the first time. Combining the advantages of the pipe roof method and the artificial ground freezing method, this method could form a “jacked pipe-frozen soil curtain” composite support system on the tunnel section, so as to effectively achieve the dual goals of “bearing” and “water-stopping between pipes”, thereby ensuring that stability and safety during tunnel excavation. To obtain the temperature, deformation and mechanical properties of the “jacked pipe-frozen soil” composite structure, a set …


Path Planning Of Coal Mine Rescue Robot Based On Improved A* Algorithm, Zhang Weimin, Zhang Yue, Zhang Hui Dec 2022

Path Planning Of Coal Mine Rescue Robot Based On Improved A* Algorithm, Zhang Weimin, Zhang Yue, Zhang Hui

Coal Geology & Exploration

A coal mine rescue robot that performs a rescue task needs to obtain the environment model and plan a collision-free path from the current location to the target location with the built-in algorithm upon receiving a task instruction. In order to reduce the moving time of the rescue robot, the path is usually required to be time-optimal. However, the path planned by the conventional A* algorithm that is widely used at present under the grid map environment has many problems, such as many path redundancy points and large turning angle, which leads to the fact that the path is suboptimal …


Fault Diagnosis Of Hydraulic Power System For Coal Mine Tunnel Drilling Rig Based On T-S Fuzzy Fault Tree, Liu Ruojun, Zhang Youzhen, Yao Ke Dec 2022

Fault Diagnosis Of Hydraulic Power System For Coal Mine Tunnel Drilling Rig Based On T-S Fuzzy Fault Tree, Liu Ruojun, Zhang Youzhen, Yao Ke

Coal Geology & Exploration

In view of the problems of fuzzy logic relation between the elements of the system, the polymorphism of fault mode, and the difficulty in obtaining the fault probability as a result of the complication of the hydraulic power system for coal mine tunnel drilling rig, a fault diagnosis method of hydraulic power system for coal mine tunnel drilling rig based on Takagi-Sugeno (T-S) fuzzy tree was proposed to overcome the limitations of traditional fault tree in fault diagnosis and analysis of the complex electromechanical hydraulic equipment. The method could timely and accurately obtain the fault information of equipment, and to …


Theory And Experiment Of The Dual-Bit Torque Self-Balancing Drilling System For Rescue Drilling, Gao Ke, Zhang Cong, Zhao Yan, Li Xu, Wen Yumin, Lyu Xiaoshu, Xie Xiaobo Nov 2022

Theory And Experiment Of The Dual-Bit Torque Self-Balancing Drilling System For Rescue Drilling, Gao Ke, Zhang Cong, Zhao Yan, Li Xu, Wen Yumin, Lyu Xiaoshu, Xie Xiaobo

Coal Geology & Exploration

The rapid and safe construction of rescue channel is an effective method to save the trapped person underground after mine accidents. The conventional rescue hole drilling technologies mainly include the downhole hammer percussion drilling technology and the composite drilling technology, which have the disadvantages of large rig structure, complex drilling process, great disturbance to the formation and low target hit rate. In particular, it is easy to have secondary accidents in the fractured strata, and the rescue requirements could not be effectively met. In order to ensure the formation adaptability and wall stability of rescue boreholes, the dual-bit torque self-balancing …


Occurrence Characteristics And Ecological Risk Assessment Of Heavy Metals In Fly Ash Of Ningdong Energy Chemical Industry Base, Zhang Zhiguo, Tan Yuning, Hu Youbiao, Zheng Yonghong, Chen Denghong, Cai Weiqing, Li Yating, Lu Jiangwei Nov 2022

Occurrence Characteristics And Ecological Risk Assessment Of Heavy Metals In Fly Ash Of Ningdong Energy Chemical Industry Base, Zhang Zhiguo, Tan Yuning, Hu Youbiao, Zheng Yonghong, Chen Denghong, Cai Weiqing, Li Yating, Lu Jiangwei

Coal Geology & Exploration

In order to expand the resource utilization of fly ash, research was conducted based on the fly ash of Yuanyang Lake Power Plant in the Ningdong Energy Chemical Industry Base. Specifically, the physical and chemical properties of fly ash were characterized and analyzed by means of scanning electron microscope, energy spectrum analysis and X-ray diffraction. Besides, the total amount, effective state and content in different forms of Pb, Cr, Ni, Cu, Cd and As in fly ash were determined through acid digestion, DTPA extraction and 5-step Tessier sequential extraction. In addition, the ecological risk of heavy metals in fly ash …


Quantitative Experimental Study On Time-Varying Characteristics Of Bleeding Of Cement-Based Grouting Materials, Zhang Runqi, Xu Bin, Yin Shangxian, Li Shuxia, Chang Yongwang, Lian Huiqing, Cao Min Nov 2022

Quantitative Experimental Study On Time-Varying Characteristics Of Bleeding Of Cement-Based Grouting Materials, Zhang Runqi, Xu Bin, Yin Shangxian, Li Shuxia, Chang Yongwang, Lian Huiqing, Cao Min

Coal Geology & Exploration

Cement-based cementitious materials are the most common grouting materials for grouting engineering. This type of material has obvious water separation effect, and obtaining the quantitative formula of water separation thickness will be helpful to improve the calculation accuracy of slurry diffusion radius. By observing the water separation process of three admixtures, namely pyrophyllite powder (0%-35%), polyvinyl alcohol (0%-8%) and fly ash (0%-90%) in cement-based slurry, the water separating rate, stone formation rate, final water separation time and water separation thickness of the three admixtures were obtained. It is found that the water separation thickness of the slurry varies regularly with …