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3d Geological Model Construction And Error Analysis Of Intelligent Mining Working Face, Wang Xinmiao, Han Baoshan, Song Tao, Shen Kai, Yue Hui, Lei Xiaoyu Apr 2021

3d Geological Model Construction And Error Analysis Of Intelligent Mining Working Face, Wang Xinmiao, Han Baoshan, Song Tao, Shen Kai, Yue Hui, Lei Xiaoyu

Coal Geology & Exploration

The complexity of geological conditions is one of the key issues affecting the further development of current intelligent mining, and there is an urgent need to build a high-precision 3D geological model of the mining face. This article analyzes the construction method of the intelligent mining geological model, and takes an intelligent working face of Huangling No.1 Mine as an example, combines all the geological exploration data of the working face, and uses the TIM-3D modeling software to construct the initial static model and the working face respectively. The dynamic model of the working face is equipped with a transparent …


Different-Source Prediction Of Gas Emission Based On Sapso-Elm And Its Application, Ren Haifeng, Yan Youji, Wu Qinghai Apr 2021

Different-Source Prediction Of Gas Emission Based On Sapso-Elm And Its Application, Ren Haifeng, Yan Youji, Wu Qinghai

Coal Geology & Exploration

In order to improve the accuracy of gas emission prediction, in view of the multiple correlations and complexity of the influencing factors of gas emission, principal component analysis and separated source prediction theory were combined, the gas emission data of the mining layer, adjacent layer, and goaf were respectively subjected to principal component analysis to reduce dimensionality, and the predictor was obtained. Aiming at the problem that the input weight matrix and hidden layer threshold of the extreme learning machine were generated randomly, the simulated annealing particle swarm optimization algorithm was used to optimize the parameters of the extreme learning …


Multi-Level Fuzzy Mathematics-Based Comprehensive Evaluation Model Of Cbm Well Productivity, Feng Yulong, Zhou Linyuan, Wang Qian, Liu Chengrui Apr 2021

Multi-Level Fuzzy Mathematics-Based Comprehensive Evaluation Model Of Cbm Well Productivity, Feng Yulong, Zhou Linyuan, Wang Qian, Liu Chengrui

Coal Geology & Exploration

To accurately predict the productivity of CBM wells, a multi-level fuzzy mathematics method was used to establish a comprehensive evaluation model including 3 secondary evaluation parameters(i.e. resource conditions, development conditions, and transformation processes) and 10 tertiary evaluation parameters. Combined with the data of reservoir parameters and stimulation technologies of 15 coalbed methane target blocks in China, the comprehensive evaluation work was carried out using the model. Finally, the actual production of each block was collected to verify the evaluation results, and the corresponding relationship between the evaluation results and the production was obtained. The results show that, the average daily …


Geochemical Characteristics And Genesis Of Coalbed Methane In Baode Area, Li Yangbing, Zeng Lei, Hu Weiqiang, Chen Xin, Ma Litao, Liu Cheng, Huang Ying, Qiao Fang Apr 2021

Geochemical Characteristics And Genesis Of Coalbed Methane In Baode Area, Li Yangbing, Zeng Lei, Hu Weiqiang, Chen Xin, Ma Litao, Liu Cheng, Huang Ying, Qiao Fang

Coal Geology & Exploration

In order to find out the geochemical characteristics and origins of coalbed methane(CBM)in Baode area, coal, CBM and water samples were collected, gas component analysis, quality detection of CBM well-produced water and stable isotope analysis were carried out. The results show that CH4 is the main hydrocarbon gas in CBM composition and its volume fraction ranges from 88.60% to 97.59%; a small amount of ethane is contained, and the volume fraction is only 0.01%-0.14%. The drying coefficient is greater than 0.99, the CBM belongs to the extremely dry CBM. The non-hydrocarbon components mainly contain CO2 and N2 …


Characteristics Of Shale Gas Reservoir In Upper Paleozoic Coal Measures In Yangquan Block, Qinshui Basin, Li Yangyang, Li Xianqing, Zhang Xueqing, Xiao Xianming, Yu Zhenfeng, Wang Baoyu Apr 2021

Characteristics Of Shale Gas Reservoir In Upper Paleozoic Coal Measures In Yangquan Block, Qinshui Basin, Li Yangyang, Li Xianqing, Zhang Xueqing, Xiao Xianming, Yu Zhenfeng, Wang Baoyu

Coal Geology & Exploration

Shale reservoir characteristics are the basic content of shale gas storage capacity evaluation. In order to explore the properties of high-evolved coal-measures shale gas reservoirs and optimize favorable reservoirs, various experimental methods of rock pyrolysis, X-ray diffraction, scanning electron microscopy, high-pressure mercury intrusion, low-temperature N2 and CO2 gas adsorption were applied to the Qinshui Basin. Reservoir characteristics were studied with core samples of coal-measure shale core from the Upper Paleozoic in Yangquan Block. The results show that the Upper Paleozoic coal-measures shale in Yangquan Block of the Qinshui Basin has a high content of organic carbon(average TOC is …


Study On Mesozoic Magmatic Intrusion And Paleozoic Multi-Mineral Genesis Mechanism In Huanghebei Coalfield,Shandong Province, Wang Huaihong, Shen Lijun, Wang Dongdong, Zhu Yuzhen, Li Zengxue, Wang Yongjun, Mao Qiang Apr 2021

Study On Mesozoic Magmatic Intrusion And Paleozoic Multi-Mineral Genesis Mechanism In Huanghebei Coalfield,Shandong Province, Wang Huaihong, Shen Lijun, Wang Dongdong, Zhu Yuzhen, Li Zengxue, Wang Yongjun, Mao Qiang

Coal Geology & Exploration

Accumulation of various minerals is common in strata, especially in areas invaded by magma, which is more conducive to the generation and preservation of various minerals and greatly improves the exploration benefit and development value of mineral resources. Taking Huanghebei Coalfield in Shandong Province as an example, this paper studies the genesis mechanism of Mesozoic rock intrusion and Paleozoic multiple minerals(coal, coal-bed methane, coal-measure shale gas and rich iron ore). Research shows that: Huanghebei Coalfield Carboniferous-Permian Period tectonic conditions and sedimentary environment are conducive to the development of coal seam, and coal seam distribution in the plane is characterized by …


Mechanism And Control Of Strong Ground Pressure In Fully Mechanized Mining Face, Zhang Yin, Zhao Yi, Li Hao Apr 2021

Mechanism And Control Of Strong Ground Pressure In Fully Mechanized Mining Face, Zhang Yin, Zhao Yi, Li Hao

Coal Geology & Exploration

In order to ensure the safe use of the withdrawal roadway in the fully mechanized mining face of thick coal seam, taking the strong ground pressure behavior of the withdrawal roadway in 31102 working face of Nalinhe No.2 well as the method of combination of field monitoring and theoretical analysis, the strong ground pressure behavior of the withdrawal roadway in the mining process of fully mechanized mining face in thick coal seam was studied. The results show that: the strong ground pressure behavior of withdrawal roadway in fully mechanized mining face of thick coal seam is mainly the result of …


Evaluation Of The Development Potential Of The Coalbed Methane Resources In Mining Area Based On Ahp-Entropy Method, Jia Zhichao, Huang Huazhou, Huang Shaobo, Zhou Yu, Wang Bo Apr 2021

Evaluation Of The Development Potential Of The Coalbed Methane Resources In Mining Area Based On Ahp-Entropy Method, Jia Zhichao, Huang Huazhou, Huang Shaobo, Zhou Yu, Wang Bo

Coal Geology & Exploration

The development of coalbed methane(CBM) in mining area is conductive to the efficient mining of pressure relief CBM in mining panels, and it reduces the risk level of underground gas. However, the difference in geological and coal mining conditions makes the development effect of surface wells quite different. Therefore, it is of guiding significance to evaluate the pre-mining panel selection. In order to explore an efficient selection method of CBM in mining areas, a complete evaluation system of CBM development potential in mining area is established by building one vote veto system and evaluation index system, combining analytic hierarchy process(AHP) …


Discussion On Roof Water Loss Control Method Of Coal Seam Based On Pre-Splitting Grouting Reformation(P-G), Zhao Chunhu, Wang Hao, Jin Dewu Apr 2021

Discussion On Roof Water Loss Control Method Of Coal Seam Based On Pre-Splitting Grouting Reformation(P-G), Zhao Chunhu, Wang Hao, Jin Dewu

Coal Geology & Exploration

In view of the technical requirements of roof water disaster prevention and water resources collaborative protection faced by coal mining in western coal mining area, this paper puts forward a technical idea of roof water loss control based on pre-splitting grouting reformation(P-G) according to the strain strength theory of material mechanics and the statistical results of mining fracture zones of different overburden types. The basic principle is that the continuous bedrock layer will be fractured into discontinuous rock layers by fracturing technology, and by weakening the “tip effect” of upward expansion of mining induced water flowing fracture in hard rock …


Comprehensive Exploration Of Collaps Column And Three-Dimensional Construction Technology Of Water Plug Based On Directional Horizontal Drilling, Tian Gan, Nan Shenghui, Lin Xudong, Fan Juan Apr 2021

Comprehensive Exploration Of Collaps Column And Three-Dimensional Construction Technology Of Water Plug Based On Directional Horizontal Drilling, Tian Gan, Nan Shenghui, Lin Xudong, Fan Juan

Coal Geology & Exploration

The Ordovician limestone water inrush from floor caused by water-conducted collapse columns is the main water hazard threat in Tashan Mine of Tongmei Group. Water inrush from collapse columns once happened in the roadway excavation of 8228 working face. On the basis of comprehensive geophysical exploration above and below the well, the development boundary, the influence zone, the cementation of the fractured body and the distribution characteristics of the water flowing subsided column are found out by means of multi-layer and multi-branch surface directional horizontal drilling speed logging, drilling fluid leakage, cuttings logging and logging while drilling, and combined with …


Effect Of Arbuscular Mycorrhizal Fungi And Hippophae Rhamnoides On The Improvement Of The Dump Of Open-Pit Coal Mine In The Eastern Grassland, Miao Chunguang, Yang Huihui, Bi Yinli, Song Ziheng, Guo Nan Apr 2021

Effect Of Arbuscular Mycorrhizal Fungi And Hippophae Rhamnoides On The Improvement Of The Dump Of Open-Pit Coal Mine In The Eastern Grassland, Miao Chunguang, Yang Huihui, Bi Yinli, Song Ziheng, Guo Nan

Coal Geology & Exploration

The land barren, grassland degradation and difficult ecological restoration are serious in the open-pit mining area of eastern China. The symbiosis between arbuscular mycorrhizal fungi(AMF) and Hippophae rhamnoides and the effect of mycorrhiza on the development of Hippophae rhamnoides root system and the improvement of soil in the dumping site were analyzed. It was found that the plant height and crown width of inoculated AMF(+M) were increased by 20% and 21%, respectively. The root length and root volume of +M were 1.46 and 1.97 times of CK, respectively. The content of Glomalin in the rhizosphere soil of Hippophae rhamnoides in …


Analysis Of Geophone Array Method In Low Snr Complex Area Of Ordos Basin, Wang Zhengliang, Xiao Guoqiang, Fu Qunli, Lyu Zhenchuan, Yao Zonghui, Shi Qingyang, Gao Bin, Yi Hongbin, Gao Qiang, Zhang Peng, Hou Jie, Shi Bingcheng, Wang Yanduo, Jiao Guixing Apr 2021

Analysis Of Geophone Array Method In Low Snr Complex Area Of Ordos Basin, Wang Zhengliang, Xiao Guoqiang, Fu Qunli, Lyu Zhenchuan, Yao Zonghui, Shi Qingyang, Gao Bin, Yi Hongbin, Gao Qiang, Zhang Peng, Hou Jie, Shi Bingcheng, Wang Yanduo, Jiao Guixing

Coal Geology & Exploration

In the northwest of Ordos Basin, there is serious random interference in the complex area, which leads to the low signal-to-noise ratio of seismic data in this area. In order to solve the problem of low signal-to-noise ratio(SNR) of seismic data in this area, a method study of suppressing random interference by geophone array is carried. The influence of random interference on the accurate calculation of NMO correction and static correction, the suppression of interference wave by geophone array, the influence of intra group height difference and array base distance on high frequency of seismic acquisition data are studied, and …


Forward Simulation Of Fault Detection By Transmitting Channel Wave In Thin Alternating Coal Seams, Ma Yanlong Apr 2021

Forward Simulation Of Fault Detection By Transmitting Channel Wave In Thin Alternating Coal Seams, Ma Yanlong

Coal Geology & Exploration

In order to study the feasibility of the fault detection by transmitting channel wave in thin alternating coal seams of southwestern region, a representative area was selected, and a coal mine in Panzhihua Coal Industry Group was selected as the research object. A three-dimensional geological model with three alternating coal seams containing three partings, three partings and faults and without parting was established based on actual geological data. Through the forward simulation and analysis of the characteristics of the wave field and the frequency dispersion of the channel waves of the three dimensional elastic wave, the validity of the amplitude …


Difficulties And Optimization Of Wire-Line Core Drilling Technology For Broken Formation In Complex Structure Area Of Northwest Hunan, Kong Xiangwang, Zhang Shaohe, Wang Wenbin, Sun Pinghe, Wu Dongyu, Xiao Jincheng, He Hongsheng Apr 2021

Difficulties And Optimization Of Wire-Line Core Drilling Technology For Broken Formation In Complex Structure Area Of Northwest Hunan, Kong Xiangwang, Zhang Shaohe, Wang Wenbin, Sun Pinghe, Wu Dongyu, Xiao Jincheng, He Hongsheng

Coal Geology & Exploration

Taking Xiangcidi 1 Well in the complex structural area of northwest Hunan as an example, in view of the common drilling difficulties encountered during the drilling process such as low core adoption rate and stuck-drilling buried drilling, we adopted the self-developed pumpless reverse circulation advanced side spray line and optimized the drilling fluid system to effectively improve the core drilling rate of the drilling project. The new type of drilling tool can form a local reverse circulation at the bottom of the hole, and combined with the internal anti-clogging cone net of the drilling tool and the design of the …


Construction And Application Of Remote Service Cloud Platform For Mine Water Hazard Prevention And Control, Wang Hao, Dong Shuning, Qiao Wei, Ji Yadong, Zhu Kaipeng, Zhou Zhenfang, Ning Dianyan, Shang Hongbo Feb 2021

Construction And Application Of Remote Service Cloud Platform For Mine Water Hazard Prevention And Control, Wang Hao, Dong Shuning, Qiao Wei, Ji Yadong, Zhu Kaipeng, Zhou Zhenfang, Ning Dianyan, Shang Hongbo

Coal Geology & Exploration

Coal mine water disaster restricts the safe and efficient development of coal resources seriously. Aiming at the typical problems of roof, floor and goaf mine water disaster at present, three aspects of mine water prevention and control in China has been carried out including water hazard assessment, water inflow prediction, water hazard early warning, and water hazard detection and control, etc. However, the intelligence of these prevention and control work is relatively low. In order to solve this problem, this paper developed a multi-data fusion remote service cloud platform for mine water disaster prevention and control combining with the integration …


Distribution And Occurrence Of Uranium In Coal And Its Migration Behavior During The Coal Utilization, Wang Wenfeng, Wang Wenlong, Liu Shuangshuang, Bai Hongyang, Wang Yulong, Duan Piaopiao, Qin Kemin, Chen Yilin Feb 2021

Distribution And Occurrence Of Uranium In Coal And Its Migration Behavior During The Coal Utilization, Wang Wenfeng, Wang Wenlong, Liu Shuangshuang, Bai Hongyang, Wang Yulong, Duan Piaopiao, Qin Kemin, Chen Yilin

Coal Geology & Exploration

Coal and uranium resources are closely related in spatial disposition as well as mineralization, and the reasonable development, utilization and pollution control of them play an essential role in the sustainable development of our national economy and society. Based on a large number of literature research and the previous results of our research group, some conclusions were drawn with regard to the distribution and occurrence of uranium in coal `and its migration in the process of coal preparation, combustion and leaching:(1) The enrichment and mineralization of uranium in coal has reflected the evolution of coal-forming tectonics:The U-rich coal in Southwest …


Evaluation Of The Hydro-Fracturing Potential For Coalbed Methane Reservoir: A Case Study Of Zhengzhuang Cbm Field, Yao Yanbin, Wang Hui, Yang Yanhui, Liu Dameng, Lu Xiuqin, Cao Lutong Feb 2021

Evaluation Of The Hydro-Fracturing Potential For Coalbed Methane Reservoir: A Case Study Of Zhengzhuang Cbm Field, Yao Yanbin, Wang Hui, Yang Yanhui, Liu Dameng, Lu Xiuqin, Cao Lutong

Coal Geology & Exploration

The "double low" rate of exploration and utilization of CBM resources in China leads to a significant slowdown in CBM production, which has become a bottleneck restricting the development of CBM industry in China. The common CBM reservoir evaluation method did not pay enough attention to the hydro-fracturing potential, resulting in low discovery rate of high-quality gas reserves and low mobilization-rate of the present reserves. Thus, it is extremely necessary to do some research regarding to hydro-fracturing potential evaluation. Targeting on the Zhengzhuang CBM field of the southern Qinshui Basin, this study did comprehensive investigations including coal core analysis, physical …


Study On Density Of The Supercritical Methane, Zhang Xinbin, Song Dangyu, Li Yunbo, Qi Yong'an, Fan Shunli Feb 2021

Study On Density Of The Supercritical Methane, Zhang Xinbin, Song Dangyu, Li Yunbo, Qi Yong'an, Fan Shunli

Coal Geology & Exploration

The density of supercritical methane is not only an important parameter for calculation of unconventional natural gas resources and adsorption capacity of methane in coal, but also a main indicator for measurement of the diffusion efficiency of supercritical methane and the ability to dissolve organic matter. Through analysis and comparison of the applicability of various gas state equations, it is realized that the Helmholtz energy state equation can accurately calculate the density of methane under the conditions of 0-30 MPa and 270-360 K. A calculation program for methane density was written using Microsoft Office Excel, and the error was less …


Framework On Intelligent Decision Support System For Coal Seam Floor Water Hazard Prevention And Control, Jin Dewu, Li Peng Feb 2021

Framework On Intelligent Decision Support System For Coal Seam Floor Water Hazard Prevention And Control, Jin Dewu, Li Peng

Coal Geology & Exploration

Coal floor water inrush is a common type of water disaster in the production process of coal mines in North China coalfield. In order to solve the scientific decision making problem of water hazard prevention and control engineering and further improve the reliability of the relevant projects, this paper puts forward a technical idea of establishing an intelligent decision support system(IDSS). The IDSS is a combination of the traditional decision support system(DSS) and artificial intelligence. On the basis of analyzing the functional requirements of DSS for water hazard prevention and control, an integrated design process of "data-model-solution" is proposed, and …


Deep Mining Under Safe Water Pressure Of Aquifer: Inheritance And Innovation, Yin Shangxian, Lian Huiqing, Xu Bin, Tian Wuzi, Cao Min, Yao Hui, Meng Haopeng Feb 2021

Deep Mining Under Safe Water Pressure Of Aquifer: Inheritance And Innovation, Yin Shangxian, Lian Huiqing, Xu Bin, Tian Wuzi, Cao Min, Yao Hui, Meng Haopeng

Coal Geology & Exploration

The paper reviews the development course of inheritance and innovation of mining under pressure, expounds the concept and the necessary and sufficient conditions of mining under pressure, and on the basis of the connotation of mining under pressure, the base level of erosion is defined as the boundary(interface) of shallow and deep mining under pressure. The paper clarified that mining above confined water is mining under pressure, while mining under aquifer does not belong to the category, and corrects the improper expression of roof and floor pressure in "Coal Mine Safety Regulations". This paper summarizes the theory and technology directly …


Comprehensive Testing Research On Floor Damage Characteristics Of Mining Extra-Thick Seam In Jungar Coalfield, Zhang Pingsong, Liu Chang, Ou Yuanchao, Sun Binyang, Xu Shi'ang, Li Shenglin Feb 2021

Comprehensive Testing Research On Floor Damage Characteristics Of Mining Extra-Thick Seam In Jungar Coalfield, Zhang Pingsong, Liu Chang, Ou Yuanchao, Sun Binyang, Xu Shi'ang, Li Shenglin

Coal Geology & Exploration

The 6th coal seam of the Carboniferous Permian in a coal mine in the Ordos Basin of Inner Mongolia is an extra-thick coal seam with an average minable thickness of 17.0 m. Its floor is threatened by limestone water. Distributed sensing optical fiber technology and cross-hole resistivity CT in situ comprehensive testing technology were used in the field, and the response characteristics of strain field and geoelectric field were obtained successively during mining. Combined with the threshold value of the discriminant parameter for loading deformation and failure of rock samples and detection section of practice, the monitoring data of the …


The Evolution Difference Of Macromolecular Structures And Its Dynamic Mechanism Of Coal Macerals:Research Status And Prospect, Cao Daiyong, Wei Yingchun, Wang Anmin, Wang Lu, Liu Zhifei, Qin Rongfang, Shu Zhenyu, Chen Gaojian Feb 2021

The Evolution Difference Of Macromolecular Structures And Its Dynamic Mechanism Of Coal Macerals:Research Status And Prospect, Cao Daiyong, Wei Yingchun, Wang Anmin, Wang Lu, Liu Zhifei, Qin Rongfang, Shu Zhenyu, Chen Gaojian

Coal Geology & Exploration

The physical and chemical properties of macerals are important factors affecting the clean and efficient utilization of coal and the physical properties of coal reservoirs. It has been recognized that the essential cause of determining the properties of macerals lies in their macromolecular structure. In order to reveal the evolution characteristics of macromolecular structure of macerals and its controlling factors, the research progresses at home and abroad were summarized and the shortcomings were analyzed from several aspects, such as the chemical and physical structure of macromolecules, the tectonic stress effect on the macromolecular evolution, and the evolution characteristics of macromolecules …


Experimental Study On The Influence Of Co2 Injection Pressure On Gas Diffusion Coefficient, Zhou Xihua, Han Mingxu, Bai Gang, Lan Anchang, Fu Zhihao Feb 2021

Experimental Study On The Influence Of Co2 Injection Pressure On Gas Diffusion Coefficient, Zhou Xihua, Han Mingxu, Bai Gang, Lan Anchang, Fu Zhihao

Coal Geology & Exploration

Most of the coal seams in China are characterized by low pressure, low permeability and low saturation. The methane gas in the coal seam is slowly desorbed and diffused slowly, which affects the production rate of coalbed methane. The coal samples from Zhaozhuang Coal Mine of Jinmei Group were selected to study the influence of different gas injection pressure on CH4 displacement process and the variation law of CH4 diffusion coefficient in the process of displacement. Independently developed CO2 displacement CH4 test platform was used to carry out the experiments under different gas injection pressures such …


Variation Law And Estimation Model Of Permeability Coefficient In Unconsolidated Confined Aquifer, Chen Luwang, Peng Zhihong, Wang Yingxin, Ge Rutao, Li Ruirui Feb 2021

Variation Law And Estimation Model Of Permeability Coefficient In Unconsolidated Confined Aquifer, Chen Luwang, Peng Zhihong, Wang Yingxin, Ge Rutao, Li Ruirui

Coal Geology & Exploration

The coal measure strata in the concealed coalfields in North China are generally covered by the Quaternary loose soils. Many hydrogeological hazards, such as mine water inrush, surface subsidence and wellbore deformation failure, have occurred in mining under unconsolidated confined aquifer, which has caused huge economic losses and casualties. The permeability coefficient is an important parameter that reflects the permeability of soil medium in the unconsolidated confined aquifer. A reasonable estimation of its values has important guiding significance for the prevention and control of such hydrogeological hazards. At present, the permeability coefficient of the unconsolidated confined aquifer in the concealed …


Characteristics And Distribution Laws Of Electric Potential Response To Mining Failure Of Deep Coal Seam, Wang Enyuan, Li Zhonghui, Niu Yue, Liu Shengdong, Shen Rongxi, Li Dexing, Zhang Xin Feb 2021

Characteristics And Distribution Laws Of Electric Potential Response To Mining Failure Of Deep Coal Seam, Wang Enyuan, Li Zhonghui, Niu Yue, Liu Shengdong, Shen Rongxi, Li Dexing, Zhang Xin

Coal Geology & Exploration

To study the response characteristics and laws on electric potential(EP) signal of the coal body in the mining failure process, a self-developed mine EP meter was utilized to conduct field tests in the No. 25050 fully mechanized mining face of Xuehu Coal Mine. The results show that the EP signals can be produced significantly during coal seam mining failure process, and the EP response characteristics can reveal the changes of stress state in coal body. As the working face advances, the EP intensity firstly increases and then decreases. The EP intensity decreases significantly after the construction of stress-relief drillings. Simultaneously, …


Research Progress Of Laser Drilling Technology In Coal Petrography, Wang Yudan, Luo Yaokun, Wen Guojun, Wu Lingling, Guan Donglin, Yao Zou Feb 2021

Research Progress Of Laser Drilling Technology In Coal Petrography, Wang Yudan, Luo Yaokun, Wen Guojun, Wu Lingling, Guan Donglin, Yao Zou

Coal Geology & Exploration

As an innovative technology with great potential in rock drilling, laser drilling has attracted great attention in research. Laser drilling is a non-contact drilling technology, which has little disturbance and damage to broken and soft formation. Thus, laser drilling can play a significant role in directional drilling of coalbed methane. This paper combs and summarizes the hole forming mechanism and influencing factors of drilling effect of laser drilling in coal petrograph. In the process of laser drilling, the interaction between laser and coal is accompanied by complex physical and chemical effects. It is pointed out that the main hole formation …


Unsupervised Noise Suppression Method For Depth Network Seismic Data Based On Prior Information Constraint, Chen Wenchao, Liu Dawei, Wei Xinjian, Wang Xiaokai, Chen Dewu, Li Shuping, Li Dong Feb 2021

Unsupervised Noise Suppression Method For Depth Network Seismic Data Based On Prior Information Constraint, Chen Wenchao, Liu Dawei, Wei Xinjian, Wang Xiaokai, Chen Dewu, Li Shuping, Li Dong

Coal Geology & Exploration

Seismic data processing is a critical step in seismic exploration. Due to the complexity of underground structure and surface conditions, seismic data processing needs to go through a series of complex processes, thus forming various types of seismic data. Different types of seismic data have different data characteristics. Exploring and making full use of the data characteristics can not only give full play to the technical potential of processing methods, eliminate the influence of various non-geological factors on the quality of seismic data processing, but also enhance the reliability of seismic data processing. Improving the signal-to-noise ratio and resolution of …


Validity Analysis Of Flow Field Method In Detecting Seepage Vector Distribution Of Earth-Rock Dam, Dai Qianwei, Cui Yongsheng, Han Xingjin, Lei Yi, Li Jiepeng, Zhu Zelong Feb 2021

Validity Analysis Of Flow Field Method In Detecting Seepage Vector Distribution Of Earth-Rock Dam, Dai Qianwei, Cui Yongsheng, Han Xingjin, Lei Yi, Li Jiepeng, Zhu Zelong

Coal Geology & Exploration

Based on the similarity between the electric potential differential control equations of the current field and velocity potential differential control equations of the seepage field, the flow field method(FFM) can not only determine the seepage by measuring the distribution of current field, but also can efficiently figure out the leakage location of the dam. For further discovering the vector distribution and direction of seepage more accurately, the horizontal and vertical potential difference between the upstream and the downstream can be measured to simulate the vector distribution of seepage. In this paper, we illustrate the principle of vector flow field method(VFFM) …


Effects Of Alternating Stress On Casing Damage Mechanism, An Fengchen, Zhang Feiyang, Yi Hao, Zhang Sui'an Feb 2021

Effects Of Alternating Stress On Casing Damage Mechanism, An Fengchen, Zhang Feiyang, Yi Hao, Zhang Sui'an

Coal Geology & Exploration

Horizontal well staged fracturing technology of horizontal well has been widely used in the exploitation of low-permeability oil and gas reservoirs and coalbed methane, and has achieved good economic results. However, the vertical section of the casing is found to be damaged with serious deformation in the process of multi-stage hydraulic fracturing, which will prevent bridge plugs from being installed at the preferred design depths, thereby resulting in abandonment of all remaining fracturing stages. In this study, a user element is developed to simulate the mechanical behavior at the casing-cement sheath interface under cyclic loads. The developed element is then …


Table Of Contents, The Editors Feb 2021

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.