Sustainability Commons^™

Physical Modeling Of Seismic Response For The Coal Seams Of Yan'an Formation In Loess Tableland Of North China, Xing Tingdong, Xue Shigui, Li Xiaowei, Suo Chonghui, Wang Huiming, Jiao Yanyan

Coal Geology & Exploration

A seismic physical simulation is carried out for the complex seismic response of the coal seam of Yan'an Formation in the loess tableland. First, the physical model materials for the dry layer near the surface of the loess tableland and the coal seam are developed. After several tests, a mixture of silicone rubber with silicon aerogel powder is selected to simulate the surface of the loess tableland, and the mixture with ultra-fine carbon powder added to silicone rubber is used to simulate the low-speed and low-density coal seam. Through the methods of molds control layer, layer by layer pouring, three-dimensional …

3d Seismic Physical Modeling Acquisition Technology And Its Application, Liu Qiang, Shi Xianxin, Hu Jiwu, Dong Ruijing, Lian Chenguang

Coal Geology & Exploration

Seismic physical modeling acts as a bridge between the research on seismic theoretical methods and actual seismic exploration, which is an important means of studying the propagation law of the elastic wave field and verifying the processing and interpretation methods. It plays an important role of theoretical supporting in the field of oil & gas seismic exploration. There is a great difference between coalfield and oil & gas in seismic exploration attributes, and no professional automatic seismic physical modeling system has been built in the field of coal field seismic exploration. Therefore, a large professional 3D seismic physical modeling system …

Design And Construction Of A Seismic Physical Model Of Room-Pillar Goafs In Shallow Coal Seams, Wang Pan, Zhu Shujie, Jia Qian, Jian Benqi, Lian Miaomiao, Dong Ruijing

Coal Geology & Exploration

In view of the problem of low detection accuracy of room-pillar goafs in shallow coal seams in northern Shaanxi, the seismic physical model is designed for physical simulation according to the principle of similarity ratio of geometry size and wave impedance. Through a large number of ratio tests of similar materials, the ratio of epoxy resin and silicone rubber is determined as 1 : 1.2 for similar materials of low velocity loess layer, 1 : 0.2 : 0.6 for epoxy resin, silicone rubber and talc for mudstone, 1 : 0.4 for epoxy resin and silicone rubber for coal seams, 1 …

Discussion On The Recommended Models For Resource Reuse Of Closed Coal Mines In Main Mining Areas Of Hebei Province, Yin Quanzeng, Chen Zhongshan, Feng Qiyan, Geng Lijuan, Lian Lixun, Li Fang, Liu Ning

Coal Geology & Exploration

The evaluation and the utilization of the resources of the closed coal mines have dual benefits of resources and environment, and can provide a transformation and development path for coal mining enterprises. Based on the investigation of the resources of the closed coal mines in the main mining areas of Hebei Province, through the summary of the typical cases of the resources reuse of the closed coal mines at home and abroad and in Hebei Province, this paper sums up 7 types and 19 kinds of recommended modes of the resources reuse of the closed coal mines in Hebei Province, …

Plastic Deformation-Based Constitutive Relation Of Coal Damage And Permeability Model, Wu Xuehai, Li Bobo, Wang Xin, Gao Zheng, Li Jianhua, Xu Jiang

Coal Geology & Exploration

Coal and gas outburst induced by mining disturbance is one of the main gas dynamic disasters in coal mine production. In order to systematically explore the evolution characteristics of coal damage and the law of gas seepage under mining disturbance, the whole stress strain–seepage experiment under different gas pressures was carried out. The generalized Hooke's law was modified by considering the effects of gas adsorption and thermal expansion, the plastic deformation-based constitutive relation of coal damage was established, and the piecewise permeability model considering the damage was further constructed. The results shown that the coal permeability can be divided into …

Prevention And Control Technology Of Goaf Water Hazard In Unauthorized Mining Areas Of Extremely Soft And Medium-Thick Coal Seams, Li Zhi, Zheng Shitian, Shi Zhiyuan, Wang Yuhang

Coal Geology & Exploration

Unauthorized mining in coal pit is common in China's coal industry. As the scope of unauthorized mining and the amount of accumulated water are hard to determine, the goaf water seriously threatens the safety of mining in adjacent large coal mines. In order to explore the unauthorized boundary of coalpits quickly and accurately and prevent the threat of goaf water, the long distance drilling technology of ground bedding borehole in medium and thick coal seam is proposed based on the controllable trajectory and accurate positioning of ground directional drilling, which mainly includes precise drilling in extremely soft and medium-thick coal …

Prediction Model Of Water Inrush From Coal Floor Based On Ga-Bp Neural Network Optimized By Ssa And Its Application, Yin Huiyong, Zhou Xinlong, Lang Ning, Zhang Lifeng, Wang Mingli, Wu Tao, Li Xin

Coal Geology & Exploration

With the increase of coal mining depth, coal production process is faced with complex water inrush mechanism and variable water inrush main control factors, and the uncertainties among the factors make the prediction of floor water inrush more difficult. In order to accurately predict the risk of floor water inrush, aiming at the small sample and non-linear problem of floor water inrush, firstly, genetic Algorithm is used to optimize the initial weights and thresholds of network random assignment, and then Sparrow Search Algorithm with strong search ability and good stability is selected to optimize the weights and thresholds for the …

Interfacial Shear Behavior Of Gabion Reinforced Coal Gangue And Stability Of Embankment Slope, Yang Guolin, Chen Zi'ang, Duan Junyi, Zhang Yu, Zhang Zhen

Coal Geology & Exploration

In order to make full use of coal gangue generated in coal mining and support the carbon neutral policy, the road section K128+573–K128+740 of Anshao Highway (Anhua-shaoyang, Hunan Province)was filled by coal gangue, and the embankment slope was enhanced by gabion net. The basic characteristics of coal gangue were obtained by its chemical composition and gradation, and shear characteristics of gabion reinforced coal gangue were tested by large-scale direct shearing instrument. Finally, the influence of reinforcement and its method on the stability of reinforced coal gangue embankment was found out by finite difference method. The experimental results show that after …

Application Of Unmanned Aerial Vehicle In Surface Soil Characterization And Geological Disaster Monitoring In Mining Areas, Long Linli, Liu Ying, Zhang Xuyang, Su Yongdong, Chen Xiaoyang

Coal Geology & Exploration

With the emergence and development of UAVs and the improvement of the miniaturization and intelligence of various sensor, UAVs equipped with sensors have become an efficient tool for obtaining spatial data. Because UAVs are low cost, short revisit period, fast and efficient, light and flexible, simple operation, and high temporal and spatial accuracy of image acquisition, it is widely used in mining land damage monitoring. Using "UAV, Inversion, Soil Monitoring, Surface Collapse, Ground Fissure" as keywords, this paper summarizes the academic papers of the search system in the web of science, CNKI, and Google Scholar from January 2010 to May …

The Development Law Of Surface Cracks In Shallow Coal Seam Mining Through Double Gullies Terrain, Sun Xueyang, Zhang Huixuan, Lu Mingjiao, Li Cheng, Miao Lintian

Coal Geology & Exploration

In order to protect the ecological environment of the mining area in the Yellow River Basin, the mining-induced surface crack development law was summarized from the parameters of surface crack development location and development morphology during mining of the working face passing through the double gullies terrain by using a combination of numerical simulation experiments, similar material simulation experiments and theoretical analysis in the context of the working face 125203 of Anshan Coal Mine in Miaohagu Mining Area of Fugu County. Through theoretical analysis, the relative position function T of surface cracks in shallow coal seam mining through double gullies …

Evolution Law Of The Phreatic Aquifer Water Table In The Water Intake Area Of South-To-North Water Diversion Central Line In Henan Province, Jing Zhaokai, Yan Qing, Xiao Hang, Wang Panpan, Wang Huan, Li Yang

Coal Geology & Exploration

The water supply of the South-to-North Water Diversion has presented a significant impact on the phreatic aquifer water table and the water consumption structure in the intake area of Henan Province. This paper firstly reviews the previous changes of groundwater level burial depth in the plain area of Henan Province, and by collecting and counting the monitoring results of shallow groundwater level in the receiving area of Henan Province from 2008 to 2018, we quantified and partitioned the changes of shallow groundwater level in the receiving area of Henan Province before and after the water supply of the South-to-North Water …

Research On The Coal Thickness Prediction Method Based On Vmd And Svm, Zeng Aiping, Zhang Jiawei, Ren Enming, Liu Tao, Jiang Fei, Liu Xingjin, Su Huairui

Coal Geology & Exploration

Changes in coal thickness have an important impact on safe and efficient coal mining. In order to solve the problem of large errors in coal thickness prediction results when the 3D seismic data contains noise, a method in which variable modal decomposition(VMD) and support vector machine(SVM) methods are combined for coal thickness prediction is proposed. Firstly, a coal-thickness wedge model is constructed and seismic forward modeling is performed on it. Based on the condition of thin coal seam thickness, the amplitude attribute and bandwidth attribute have a good positive correlation with the coal thickness, while the instantaneous frequency attribute has …

Research And Application Of The Prediction Method For Cbm Enrichment Area Of Low Rank Coal, Luo Zhongqin, Liu Peng, Meng Fanbin Research Institute Of Coal Geophysical Exploration, China National Administration Of Coal Geology, Zhuozhou 072750, China

Coal Geology & Exploration

The exploration of low rank coal coalbed methane(CBM) faces the problems of low resource exploration rate and low single well production. And medium and low rank coal CBM exploration is still in the primary stage. In order to improve the predition accuracy of the low rank coal CBM enrichment area, the laboratory test data of 652 coal samples from 56 wells in Hancheng, Jincheng Baode, Ji'ergalangtu Qinshui Basin, Huainan, Huaibei and other places were collected to compare the relationship between gas content and elastic parameters of high, medium and low rank coal samples. The results indicated that the correlation between …

Mechanism And Effect Analysis Of Enhanced Gas Drainage With Large Diameter Double Boreholes, Zhang Chunhua, Zhang Zijian, Nian Jun, Jiao Dengming

Coal Geology & Exploration

To study the mechanism of enhanced gas drainage with large diameter double boreholes, numerical models of single holes with different diameters and double ø350 mm holes were established by using the RFPA^2D-Gas software in working face 30110 of Shiquan Coal Mine, Shanxi Province. Stress distribution, damage and fracture, gas permeability evolution and gas migration law of the coal around the hole were analyzed, and then the extraction effect of double ø350 mm holes was investigated. Simulation results show that the pressure relief radii of the ø100 mm, ø250 mm, ø350 mm and double ø350 mm holes are 0.25 …

Factors Affecting The Attitude Accuracy Of Wireless Electromagnetic Wave Mwd System, Wang Xiaobo

Coal Geology & Exploration

In broken soft coal seams of coal mine where hydraulic driving directional drilling is used, hole collapse and hole wall instability are easy to occur. Electromagnetic wave measurement while drilling system is suitable for gas driving drilling, so it is widely used in broken soft coal seams. The accuracy of drilling trajectory is the key to gas drainage effect in broken soft coal seams. In the use of electromagnetic wave measurement while drilling system, the phenomenon of insufficient accuracy and large error of trajectory measurement appears irregularly. In order to solve this problem, this paper analyzes all the factors that …

Characteristics Of The Shale Gas Reservoirs And Evaluation Of Sweet Spots In Wufeng Formation And Longmaxi Formation In Jingmen Exploration Area, Li Xiaoming, Liu Jirong, Lin Wen, Ma Lihong, Liu Dexun, Chen Yujie

Coal Geology & Exploration

In order to further clarify the resource potential of shale gas from Wufeng Formation to Longmaxi Formation in Jingmen exploration area, sweet spots were selected. The shale in Wufeng Formation and 1th Member of Longmaxi Formation of the well X was taken as the research object in this study. Using sliced kerogen, X-ray diffraction, nuclear magnetic resonance, micro nano CT scanning, geochemical analysis and other testing methods, combined with logging interpretation results, based on the petrology, organic geochemical and mineral composition, physical properties, pore types and structure characteristics and hydrocarbon content, the reservoir characteristics of Wufeng-1^th Member of the …

Analysis Of Organic Matter Maturity Of Sapropel Coal In Oil Layer A Of Haishiwan Mine Field Of Yaojie Mining Area, Song Xiaozhong, Zhang Bingzhong, Lei Ying, Song Yanqiang

Coal Geology & Exploration

The vitrinite reflectance is recognized as the only comparable evaluation index of organic matter maturity of source rock in the exploration and development of oil and gas, shale gas and coalbed methane resources. Current research was done to determine the organic matter maturity of sapropel coal in oil layer A in Haishiwan mine field more accurately. Coal samples were collected from boreholes and observation of the optical characteristics of reflected light and fluorescence microscopic components were studied under the microscope. It was found that there are two different characteristic vitrinites in sapropel coal in oil layer A. One was fluorescent …

Deformation Characteristics Of Coal Measures And Gas Occurrence Law Of Coal Mines In North China, Wang Wei, Wei Yanzhao, Jia Tianrang, Yan Jiangwei

Coal Geology & Exploration

Gas is not only one of the important disaster-causing factors in coal mines, but also an important clean energy. Understanding the deformation characteristics of coal measures and the occurrence of gas is the basis for coal mine gas disaster prevention and coalbed methane development. Taking the North China coal measures as the research object, taking the tectonic evolution and control as the main line, using the theory of plate tectonics, tectonic evolution and step by step control of gas-occurring structures, the deformation characteristics of the North China coal-measures and the law of coal mine gas occurrence were systematically studied. The …

Discussion On The Water-Preserved Coal Mining By Dewatering-Reflooding Water Curtain In Open-Pit Coal Mines, Li Ying, Yang Zhuo, Wu Tong

Coal Geology & Exploration

To suppress the attenuation of groundwater resources caused by drainage and control the influence range of coal mining on groundwater resources, the coal mining technology with water curtain was adopted. Taking an open-pit coal mine as the background, this paper established a sand trough recharge platform to carry out physical experiments, and used a numerical method to simulate the irrigation area, so as to analyze the formation and variation of the dewatering-reflooding water curtain. Physical experiments were carried out to observe the formation of a fixed head boundary by water injection curtain which prevented the expansion of funnel, the influence …

Case Study On The Effects Of Seismic Exploration Beneath The Goafs Of Different Ages, Zhang Zhao, Yin Quanzeng

Coal Geology & Exploration

With the continuous development of coal resources, the upper group of coal in some coal mines has been mined out, and it is urgent to solve the detection problem of the lower group of coal. Affected by the goaf formed by the upper group of coal, the seismic energy absorption and scattering attenuation of the lower group of coal are significant, and the signal-to-noise ratio of the data is low. The detection of the lower group of coal under the goaf by 3D seismic exploration is still in the exploration stage. In this paper, the 3D seismic exploration project of …

Prediction Of Fracture Distribution And Evaluation Of Shale Gas Preservation Conditions In Longmaxi Formation In Dongxi Area, Xie Jiatong, Fu Xiaoping, Qin Qirong, Li Hu

Coal Geology & Exploration

Commercial development of shale gas confirmed that mature shale has great potential for exploration, southeast Sichuan is the strategic pilot area of shale gas exploration and development in southern China, cracks are the key factor of shale gas preservation and development deployment, for the structural environment complex and special basin edge area, increasing the difficulty of shale crack research, but also provides a new direction for shale gas exploration and development. As a new field of oil and gas exploration in China, shale gas exploration has not yet developed a mature crack evaluation system. Taking Dongxi area of the southeast …

Study On The Microscopic Mechanism Of The Loess Improved By Quicklime, Xie Xiao, Wang Luyao, Deng Lejuan, Zhang Guowei

Coal Geology & Exploration

To investigate the influence of lime content on loess strength and its microscopic mechanism, different proportions of lime were used to improve loess. Through direct shear test, mercury intrusion porosimetry and scanning electron microscopy, the strength characteristics and microstructure changes of compacted loess and modified loess with different lime contents were analyzed qualitatively and quantitatively, and the microscopic mechanism of lime-improved loess was analyzed in depth. The results show that the shear strength parameters of lime-improved loess increases first and then decreases with the increase of lime contents. The cohesive force and internal friction angle reach the maximum when the …

A 3d Seismic Physical Modeling System Of Large Double Triaxial Air-Supported Positioning And Multichannel Data Acquisition And Its Application, Shi Xianxin, Liu Qiang, Hu Jiwu, Wang Pan, Lian Chenguang, Jia Qian, Zhang Miaomiao, Nie Ailan

Coal Geology & Exploration

As an important technology to study seismic wave propagation characteristics, 3D seismic physical simulation is an effective method to understand the propagation law and response characteristics of seismic waves in complex structures. It has the advantages of more realistic results and no limitation on calculation methods and boundary conditions over numerical simulation. Therefore, it has important applications in the research of the basic law of seismic wave propagation, verification of field seismic exploration methods, design optimization of observation systems, etc. This paper presents a 3D seismic physical modeling system of large double triaxial air-supported positioning and multichannel data acquisition, which …

Experimental Study On Transient Electromagnetic Method With A Conical Source, Yang Haiyan, Liu Zhixin, Zhang Hua, Chen Xiao, Lian Zhe, Wang Ling, Yang Fujie

Coal Geology & Exploration

A new transmitter device-conical source has been proved theoretically to have several advantages for transient electromagnetic sounding. To verify application ability of conical source, two kinds of transmitter devices were designed and made, and the experimental studies on surface and in mine roadway were carried out. By applying high density resistivity achievements in surface experiment, the detecting results using conical source and multi-coils were compared. The results show that the description of strata resistivity with conical source is better than that with multi-coils. One fault was identified and the strike and position of which matches the high density resistivity result …

New Method And Optimization Research On Water Sealing Outside Casing Based On Water-Swelling Rubber For Stratified Pumping, Zheng Xianghua, Yuan Wei, Luo Yunxiang, Cheng Cong

Coal Geology & Exploration

Stratified pumping test is a key technique for hydrogeological exploration. To solve the problems of low efficiency and poor reliability and controllability of the traditional water-sealing methods outside casing for stratified pumping, a water-swelling rubber was developed based on high water absorption of the sodium polyacrylate resin, and a new approach based on water-swelling rubber was proposed and optimized by the response surface methodology in this paper. With the water swelling ratio of the rubber as response index, a surrogate model was constructed by the Box-Behnken experimental design to study the influence of different process parameters, working condition parameters, and …

Numerical Analysis Of The Effect Of Different Soil Types And Water Content On Heat Transfer Performance Of Horizontal Buried Pipes, Zou Hang, Pei Peng, Hao Dingyi, Wang Chen

Coal Geology & Exploration

In order to reveal the heat transfer performance of the horizontal buried pipe heat exchanger in the ground source heat pump system in different soil types, this paper, based on the theoretical knowledge of soil capillary water, combined with the means of numerical simulation, discusses the influence of the difference of three-phase composition in different types of energy storage soil on the heat transfer characteristics of the horizontal buried pipe heat exchanger. The results show that under the cooling condition of 308.15 K, the outlet water temperature of the horizontal pipe in the loam soil decreases to 303.3 K and …

Development And Prospect Of Intelligent Drilling Technology And Equipment For Underground Coal Mines In China, Li Quanxin, Liu Fei, Fang Jun Xi'an Research Institute Co., Ltd., China Coal Technology And Engineering Group Corp., Xi'an 710077, China, Liu Jianlin, Chu Zhiwei

Coal Geology & Exploration

The intelligent drilling technology and equipment are important part of the intelligent construction of coal mine, and it is the advanced technology and equipment urgently needed by coal mine enterprises to further promote the work of reducing personnel and increasing efficiency. The phased achievements of underground intelligent drilling technology and equipment during the 13th five-year plan are systematically summarized, and the development status of key technical equipment such as automatic drilling rig, parameter monitoring of measurement while drilling(MWD) system, rotary steerable system are introduced. The key factors restricting the research and development (R & D) and application of intelligent drilling …

Plastic Recycling Is Inefficient And Expensive, Clark S. Adomaitis

Capstones

Plastics production and incineration contributes more than 850 million metric tons to the emissions that are causing climate change. Emissions are growing at a moment when scientists and world leaders are in agreement that they need to dramatically decrease. Environmentalists say that plastic production makes up 4.5% of global greenhouse gas emissions. New plastic plants opening in the U.S. do not line up with emission reduction goals.

At the end of plastics’ lives, a lot of what we’re putting into our recycling bins isn’t getting recycled. In fact, only 18% of trash from New York City homes is actually recycled. …

Risk-Based Machine Learning Approaches For Probabilistic Transient Stability, Umair Shahzad

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Power systems are getting more complex than ever and are consequently operating close to their limit of stability. Moreover, with the increasing demand of renewable wind generation, and the requirement to maintain a secure power system, the importance of transient stability cannot be overestimated. Considering its significance in power system security, it is important to propose a different approach for enhancing the transient stability, considering uncertainties. Current deterministic industry practices of transient stability assessment ignore the probabilistic nature of variables (fault type, fault location, fault clearing time, etc.). These approaches typically provide a conservative criterion and can result in expensive …

A 60- Year Record Of The Demotechnic Index Of States, 1960-2019, Gavin James Kellough

Graduate Theses and Dissertations

A country’s dependency on energy resources can be interpreted through the calculation of energy indices. The Demotechnic Index (DI) was used to determine the trajectory of energy efficiency of each state in the United States over the period 1960-2019. The DI serves as a measure of the energy intensity of states and a proxy for energy sustainability of each state.The DI is the ratio of total energy use to total metabolic energy demand of a population. Mathematically, DI = (E_T-E_M)/E_M E_T represents the total energy used (metabolic energy + technological energy in kilojoules annually, kJ/y), while EM represents the basic …