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Theoretical analysis and engineering application of controllable shock wave technology for enhancing coalbed methane in soft and low‑permeability coal seams
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作者 Guodong Qiao Zegong Liu +4 位作者 Yongmin Zhang Changping Yi Kui Gao Shigui Fu Youzhi Zhao 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期123-142,共20页
Coalbed methane(CBM)is a significant factor in triggering coal and gas outburst disaster,while also serving as a clean fuel.With the increasing depth of mining operations,coal seams that exhibit high levels of gas con... Coalbed methane(CBM)is a significant factor in triggering coal and gas outburst disaster,while also serving as a clean fuel.With the increasing depth of mining operations,coal seams that exhibit high levels of gas content and low permeability have become increasingly prevalent.While controllable shockwave(CSW)technology has proven effective in enhancing CBM in laboratory settings,there is a lack of reports on its field applications in soft and low-permeability coal seams.This study establishes the governing equations for stress waves induced by CSW.Laplace numerical inversion was employed to analyse the dynamic response of the coal seam during CSW antireflection.Additionally,quantitative calculations were performed for the crushed zone,fracture zone,and effective CSW influence range,which guided the selection of field test parameters.The results of the field test unveiled a substantial improvement in the gas permeability coefficient,the average rate of pure methane flowrate,and the mean gas flowrate within a 10 m radius of the antireflection borehole.These enhancements were notable,showing increases of 3 times,13.72 times,and 11.48 times,respectively.Furthermore,the field test performed on the CSW antireflection gas extraction hole cluster demonstrated a noticeable improvement in CBM extraction.After antireflection,the maximum peak gas concentration and maximum peak pure methane flow reached 71.2%and 2.59 m^(3)/min,respectively.These findings will offer valuable guidance for the application of CSW antireflection technology in soft and low-permeability coal seams. 展开更多
关键词 CSW antireflection in coal seams CBM extraction enhancement Soft and low-permeability coal seams field test
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Surrounding Rock Failure Mechanism and Control Technology of Gob-Side Entry with Triangle Coal Pillar at Island Longwall Panel in 15 m Extra-Thick Coal Seams
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作者 Hao Sun 《World Journal of Engineering and Technology》 2024年第2期373-388,共16页
Taking the return air roadway of Tashan 8204 isolated island working face as the background, the evolution law of the stress field in the surrounding rock of the widened coal pillar area roadway during the mining peri... Taking the return air roadway of Tashan 8204 isolated island working face as the background, the evolution law of the stress field in the surrounding rock of the widened coal pillar area roadway during the mining period of the isolated island working face is obtained through numerical simulation. The hazardous area of strong mine pressure under different coal pillar widths is determined. Through simulation, it is known that when the width of the coal pillar is less than 20 m, there is large bearing capacity on the coal side of the roadway entity. The force on the side of the coal pillar is relatively small. When the width of the coal pillar ranges from 25 m to 45 m, the vertical stress on the roadway and surrounding areas is relatively high. Pressure relief measures need to be taken during mining to reduce surrounding rock stress. When the width of the coal pillar is greater than 45 m, the peak stress of the coal pillar is located in the deep part of the surrounding rock, but it still has a certain impact on the roadway. It is necessary to take pressure relief measures to transfer the stress to a deeper depth to ensure the stability of the triangular coal pillar during the safe mining period of the working face. This provides guidance for ensuring the stability of the triangular coal pillar during the safe mining period of the working face. 展开更多
关键词 Island coal Face Evolution Law of Surrounding Rock Stress field Strong Mine Pressure Hazardous Area
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Method for prevention and control of spontaneous combustion of coal seam and its application in mining field 被引量:12
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作者 Wei Lu Ying-Jiazi Cao Jerry C.Tien 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第5期839-846,共8页
Spontaneous combustion of coal seam has been and continues to be a big problem in coal mines. It could pose great threat to the safety of the whole mine and all miners, especially when it occurs in or nearby coal mine... Spontaneous combustion of coal seam has been and continues to be a big problem in coal mines. It could pose great threat to the safety of the whole mine and all miners, especially when it occurs in or nearby coal mines. Besides, environment of area surrounded mines during combustion can be threatened where large amount of toxic gases including CO_2, CO, SO_2 and H_2S can be leased by fire in mine. Hence, it is important and significant for scholars to study the controlling and preventing of the coal seam fire. In this paper, the complicated reasons for the occurrence and development of spontaneous combustion in coal seam are analysed and different models under various air leakage situations are built as well. Based on the model and approximately calculation, the difficulty of fire extinguishment in coal seam is pointed out as the difficulty and poor effect to remove the large amount of heat released. Detailed measurements about backfilling and case analyses are also provided on the basis of the recent ten years' practice of controlling spontaneous combustion in coal seams in China. A technical fire prevention and control method has been concluded as five steps including detection, prevention, sealing, injection and pressure adjustment. However, various backfill materials require different application and environmental factors, so in this paper, analyses and discussion about the effect and engineering application of prevention of spontaneous combustion are provided according to different backfilling technologies and methods. Once the aforementioned fire prevention can be widely applied and regulated in mines, green mining will be achievable concerning mine fire prevention and control. 展开更多
关键词 SPONTANEOUS COMBUSTION of coal PREVENTION and control Pressure adjustment MINING field
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Simulation of Paleotectonic Stress Fields and Distribution Prediction of Tectonic Fractures at the Hudi Coal Mine, Qinshui Basin 被引量:9
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作者 FANG Huihuang SANG Shuxun +2 位作者 WANG Jilin LIU Shiqi JU Wei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2007-2023,共17页
Study on tectonic fractures based on the inversion of tectonic stress fields is an effective method. In this study, a geological model was set up based on geological data from the Hudi Coal Mine, Qinshui Basin, a mech... Study on tectonic fractures based on the inversion of tectonic stress fields is an effective method. In this study, a geological model was set up based on geological data from the Hudi Coal Mine, Qinshui Basin, a mechanical model was established under the condition of rock mechanics and geostress, and the finite element method was used to simulate the paleotectonic stress field. Based on the Griffith and Mohr-Coulomb criterion, the distribution of tectonic fractures in the Shanxi Formation during the Indosinian, Yanshanian, and Himalayan period can be predicted with the index of comprehensive rupture rate. The results show that the acting force of the Pacific Plate and the India Plate to the North China Plate formed the direction of principal stress is N-S, NW - SE, and NE - SW, respectively, in different periods in the study area. Changes in the direction and strength of the acting force led to the regional gradients of tectonic stress magnitude, which resulted in an asymmetrical distribution state of the stress conditions in different periods. It is suggested that the low-stress areas are mainly located in the fault zones and extend along the direction of the fault zones. Furthermore, the high-stress areas are located in the junction of fold belts and the binding site of multiple folds. The development of tectonic fractures was affected by the distribution of stress intensity and the tectonic position of folds and faults, which resulted in some developed areas with level I and II. There are obvious differences in the development of tectonic fractures in the fold and fault zones and the anticline and syncline structure at the same fold zones. The tectonic fractures of the Shanxi Formation during the Himalayan period are more developed than those during the Indosinian and Yanshanian period due to the superposition of the late tectonic movement to the early tectonic movement and the differences in the magnitude and direction of stress intensity. 展开更多
关键词 tectonic fracture paleotectonic stress field comprehensive rupture rate numerical simulation Hudi coal Mine Qinshui Basin
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Spatio-temporal changes of underground coal fires during 2008-2016 in Khanh Hoa coal field(North-east of Viet Nam) using Landsat time-series data 被引量:3
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作者 Tuyen Danh VU Thanh Tien NGUYEN 《Journal of Mountain Science》 SCIE CSCD 2018年第12期2703-2720,共18页
Underground coal fires are one of the most common and serious geohazards in most coal producing countries in the world. Monitoring their spatio-temporal changes plays an important role in controlling and preventing th... Underground coal fires are one of the most common and serious geohazards in most coal producing countries in the world. Monitoring their spatio-temporal changes plays an important role in controlling and preventing the effects of coal fires, and their environmental impact. In this study, the spatio-temporal changes of underground coal fires in Khanh Hoa coal field(North-East of Viet Nam) were analyzed using Landsat time-series data during the 2008-2016 period. Based on land surface temperatures retrieved from Landsat thermal data, underground coal fires related to thermal anomalies were identified using the MEDIAN+1.5×IQR(IQR: Interquartile range) threshold technique. The locations of underground coal fires were validated using a coal fire map produced by the field survey data and cross-validated using the daytime ASTER thermal infrared imagery. Based on the fires extracted from seven Landsat thermal imageries, the spatiotemporal changes of underground coal fire areas were analyzed. The results showed that the thermalanomalous zones have been correlated with known coal fires. Cross-validation of coal fires using ASTER TIR data showed a high consistency of 79.3%. The largest coal fire area of 184.6 hectares was detected in 2010, followed by 2014(181.1 hectares) and 2016(178.5 hectares). The smaller coal fire areas were extracted with areas of 133.6 and 152.5 hectares in 2011 and 2009 respectively. Underground coal fires were mainly detected in the northern and southern part, and tend to spread to north-west of the coal field. 展开更多
关键词 UNDERGROUND coal fires SPATIO-TEMPORAL CHANGES Khanh Hoa coal field (Viet Nam) LANDSAT time-series data
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Numerical simulation of spatial distributions of mining-induced stress and fracture fields for three coal mining layouts 被引量:4
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作者 Shengwei Li Mingzhong Gao +6 位作者 Xiaojun Yang Ru Zhang Li Ren Zhaopeng Zhang Guo Li Zetian Zhang Jing Xie 《Journal of Rock Mechanics and Geotechnical Engineering》 CSCD 2018年第5期907-913,共7页
In this study, the spatial distributions of stress and fracture fields for three typical underground coal mining layouts, Le, non-pillar mining (NM), top-coal caving mining (TCM) and protective coal-seam mining (... In this study, the spatial distributions of stress and fracture fields for three typical underground coal mining layouts, Le, non-pillar mining (NM), top-coal caving mining (TCM) and protective coal-seam mining (PCM), are modeled using discrete element software UDEC, The numerical results show that different mining layouts can lead to different mining-induced stress fields, resulting in diverse fracture fields, For the PCM, the mining influenced area in front of the mining faces is the largest, and the stress concentration factor in front of the mining faces is the lowest, The spatial shapes of the mining-induced fracture fields under NM, TCM and PCM differ, and they are characterized by trapezoidal, triangular and tower shapes, respectively, The fractal dimensions of mining-induced fractures of the three mining layouts decrease in the order of PCM, TCM and NM, It is also shown that the PCM can result in a better gas control effect in coal mines with high outburst potential, The numerical results are expected to provide a basis for understanding of mining-induced gas seepage fields and provide a reference for high- efficiency coal mining, 展开更多
关键词 coal mining Mining layouts Mining-induced stress field Mining-induced fracture field Numerical simulation
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Technical parameters of drawing and coal-gangue field movements of a fully mechanized large mining height top coal caving working face 被引量:7
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作者 LIU Chang-you HUANG Bing-xiang WU Feng-feng 《Mining Science and Technology》 EI CAS 2009年第5期549-555,共7页
Under fully mechanized, large mining height top coal caving conditions, the shield beam slope angle of the support increases due to the enlargement of the top coal breaking and caving space. This results in a change o... Under fully mechanized, large mining height top coal caving conditions, the shield beam slope angle of the support increases due to the enlargement of the top coal breaking and caving space. This results in a change of the caving window location and dimensions and, therefore, the granular coal-gangue movement and flows provide new characteristics during top coal caving. The main inferences we draw are as follows. Firstly, after shifting the supports, the caved top coal layer line and the coal gangue boundary line become steeper and are clearly larger than those under common mining heights. Secondly, during the top coal caving procedure, the speed of the coal-gangue flow increases and at the same drawing interval, the distance between the coal-gangue boundary line and the top beam end is reduced. Thirdly, affected by the drawing ratio, the slope angle of the shield beam and the dimensions of the caving window, it is easy to mix the gangue. A rational drawing interval will cause the coal-gangue boundary line to be slightly behind the down tail boom lower boundary. This rational drawing interval under conditions of large mining heights has been analyzed and determined. 展开更多
关键词 large mining height top coal caving coal-gangue movement field coal caving technical parameters coal caving window
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CFD prediction of physical field for multi-air channel pulverized coal burner in rotary kiln 被引量:8
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作者 马爱纯 周孑民 +1 位作者 欧俭平 李旺兴 《Journal of Central South University of Technology》 EI 2006年第1期75-79,共5页
A 3-D numerical simulation with CFX software on physical field of multi-air channel coal burner in rotary kiln was carried out. The effects of various operational and structural parameters on flame feature and tempera... A 3-D numerical simulation with CFX software on physical field of multi-air channel coal burner in rotary kiln was carried out. The effects of various operational and structural parameters on flame feature and temperature distribution were investigated. A thermal measurement was conducted on a rotary kiln (4.5m in diameter, 90m in length) with four-air channel coal burner to determine the boundary conditions and to verify the simulation results. The calculation result shows that the distribution of velocity near burner exit is saddle-like; recirculation zones near nozzle and wall are useful for mixture primary air with coal and high temperature fume. A little central airflow can avoid coal backing up and cool nozzle. Adjusting the ratio of internal airflow to outer airflow is an effective and major means to regulate flame and temperature distribution in sintering region. Large whirlcone angle can intensify disturbution range at flame root to accelerate ignition and mixture. Large coal size can reduce high temperature region and result in coal combusting insufficiently. Too much combustion air will lengthen flame and increase heat loss. 展开更多
关键词 CFD numerical simulation CFX physical field multi-air channel coal burner rotary kiln
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Investigation on the stress field characteristic of top coal at FMTC faces under the influence of caving thickness 被引量:5
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作者 谢广祥 常聚才 杨科 《Journal of Coal Science & Engineering(China)》 2007年第2期123-125,共3页
In the background of the technology condition and the geological condition of the 1151(3) fully mechanized top-coal caving face (FMTC face), and by means of taking nonlinear 3D numerical simulation, the stress red... In the background of the technology condition and the geological condition of the 1151(3) fully mechanized top-coal caving face (FMTC face), and by means of taking nonlinear 3D numerical simulation, the stress redistribution rules of top coal with different thick coal seam were obtained by investigation on the numerical simulation of the redistributions of the stress with different coal seam's thickness. The research showes that there exists a certain difference on the stress distributions of the top coal at face, the maximum principal stress is located near to the tailentry's corner. The vertical stress's peak of the top coal decreases and the distance ahead of face position increases as the once mining thickness of the coal seam increases. At the same coal seam, the vertical stresses' peak of top coal gradually decreases from the top to the bottom, the peak's position is basically the same and its changes are gradually obvious with the thickness of coal seam increas- ing. The vertical stress of top coal places in a low stress state at a certain range ahead of face and over the face, which reveals the essence that the support loads are generally low under the condition of FMTC. The study supplies the theoretical foundation for the support design and selection, the theory of top coal's fragmentation, the movement rules of top coal and improving the recovery of top coal. 展开更多
关键词 fully mechanized top-coal caving face thickness of coal seam top coal stress field
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Effect of an electrostatic field on gas adsorption and diffusion in tectonic coal 被引量:4
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作者 Jian Kuo Lei Dongji +2 位作者 Fu Xuehai Zhang Yugui Li Hengle 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期607-613,共7页
The characteristics of adsorption, desorption, and diffusion of gas in tectonic coal are important for the prediction of coal and gas outbursts. Three types of coal samples, of which both metamorphic grade and degree ... The characteristics of adsorption, desorption, and diffusion of gas in tectonic coal are important for the prediction of coal and gas outbursts. Three types of coal samples, of which both metamorphic grade and degree of damage is different, were selected from Tongchun, Qilin, and Pingdingshan mines. Using a series of experiments in an electrostatic field, we analyzed the characteristics of gas adsorption and diffusion in tectonic coal. We found that gas adsorption in coal conforms to the Langmuir equation in an electrostatic field. Both the depth of the adsorption potential well and the coal molecular electroneg- ativity increases under the action of an electrostatic field. A Joule heating effect was caused by changing the coal-gas system conductivity in an electrostatic field. The quantity of gas adsorbed and AP result from competition between the depth of the adsorption potential well, the coal molecular electronegativ- ity, and the Joule heating effect. △P peaks when the three factors control behavior equally. Compared with anthracite, the impact of the electrostatic field on the gas diffusion capacity of middle and high rank coals is greater. Compared with the original coal, the gas adsorption quantity,△P, and the gas diffusion capacity of tectonic coal are greater in an electrostatic field. In addition, the smaller the particle size of tectonic coal, the larger the△P. 展开更多
关键词 Electrostatic field Tectonic coal Depth of adsorption potential well Joule heating effect Initial velocity of gas diffusion
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Vertical variation of trace elements and its relation to the water-bearing capacity of Ordovician strata,in Datun coal field 被引量:1
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作者 LIU Huai-zhong HAN Bao-ping 《Mining Science and Technology》 EI CAS 2009年第2期166-169,共4页
We tested for fourteen trace elements in samples collected from the Ordovician strata in Datun coal field. The vertical concentration variation of these trace dements is reported. The relationship of the variation to ... We tested for fourteen trace elements in samples collected from the Ordovician strata in Datun coal field. The vertical concentration variation of these trace dements is reported. The relationship of the variation to the water-bearing capacity of the Ordovician strata is discussed. The minimum concentration of eleven (of 14 total) trace elements appears in the lower Majiagou formation. The maximum concentrations mainly appear in the Badou and Jiawang formations: eight maxima are located in Badou and four more are in Jiawang. The study of karst development and the water-bearing capacity of Ordovician strata shows that karst is well developed in the Majiagou formation and there is a consequent high water-bearing capacity in this formation: Badou and Jiawang formations are contrary to this situation. The results illustrate that the minimum concentrations of most trace elements within certain Ordovician formations can be taken as strong evidence for the existence of a well developed karst and a high water-bearing capacity. 展开更多
关键词 ORDOVICIAN trace element water-bearing capacity Damn coal field
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STUDY ON EXTRACTING METHODS OF BURIED GEOLOGICAL INFORMATION IN HUAIBEI COAL FIELD 被引量:1
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作者 王四龙 赵学军 +3 位作者 凌贻棕 刘玉荣 宁书年 侯德文 《Journal of Coal Science & Engineering(China)》 1999年第1期11-15,共5页
It is discussed features and tbe producing mechanism of buried geological information in geological, geophysical and remote sensing data in Huaibei coal field, and studied the methods extracting buried tectonic and ig... It is discussed features and tbe producing mechanism of buried geological information in geological, geophysical and remote sensing data in Huaibei coal field, and studied the methods extracting buried tectonic and igneous rock information from various geologicaI data using digital image processing techoiques. 展开更多
关键词 Huaibei coal field geological data buried geological information digital image processing
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A back analysis of the temperature field in the combustion volume space during underground coal gasification 被引量:3
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作者 Chen Liang Hou Chaohu +1 位作者 Chen Jiansheng Xu Jiting 《Mining Science and Technology》 EI CAS 2011年第4期581-585,共5页
The exact shape and size of the gasification channel during underground coal gasification(UGC) are of vital importance for the safety and stability of the upper parts of the geological formation.In practice existing g... The exact shape and size of the gasification channel during underground coal gasification(UGC) are of vital importance for the safety and stability of the upper parts of the geological formation.In practice existing geological measurements are insufficient to obtain such information because the coal seam is typically deeply buried and the geological conditions are often complex.This paper introduces a cylindrical model for the gasification channel.The rock and soil masses are assumed to be homogeneous and isotropic and the effect of seepage on the temperature field was neglected.The theory of heat conduction was used to write the equation predicting the temperature field around the gasification channel.The idea of an excess temperature was introduced to solve the equations.Applying this model to UCG in the field for an influence radius,r,of 70 m gave the model parameters,u1,2,3...,of 2.4,5.5,8.7...By adjusting the radius(2,4,or 6 m) reasonable temperatures of the gasification channel were found for 4 m.The temperature distribution in the vertical direction,and the combustion volume,were also calculated.Comparison to field measurements shows that the results obtained from the proposed model are very close to practice. 展开更多
关键词 Underground coal gasification Gasification channel Temperature field Combustion space areaBack analysis
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The idea and project of the “Medium-Scale Experiment Field for Earthquake Prediction”──Research on observations and applications of mining earthquake in Mentougou Coal Mine
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作者 张少泉 任振启 +2 位作者 张连城 张建军 邹立晔 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第4期142-146,148-150+152-,共10页
A brief account of the development of the research on mining earthquakes and the general situation of the Mentougou Coal Mine medium scale experiment field for earthquake prediction and the project of monitor and p... A brief account of the development of the research on mining earthquakes and the general situation of the Mentougou Coal Mine medium scale experiment field for earthquake prediction and the project of monitor and prediction is given. The differences of waveforms between mining earthquakes and natural earthquakes is discussed. The magnitude frequency distribution of the 79 000 mining earthquakes of over M L1.0 from 1984 to 1995 is summarized . Finally, taking PH and PV, the principal compressive stress components of the focal mechanism of the mining earthquakes, as the criteria, analyses the stress background of the 12 large mining earthquakes. 展开更多
关键词 mining earthquakes mining seismology earthquake prediction Mentougou coal Mine medium scale experiment field for earthquake prediction.
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Application of axiomatic approach to coal mine design field
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作者 国汉军 《Journal of Coal Science & Engineering(China)》 2004年第2期95-100,共6页
Two design axioms and axiomatic approach were discussed. As an example of application, design process of a new style single prop was illustrated in term of axi- oms.
关键词 coal mine design field axiomatic single prop
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Small-scale area survey and analysis of Xinjiang's coal field fire in China
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作者 Zhong Maohua Fu Tairan Hu Zhongbin 《Engineering Sciences》 EI 2008年第3期57-63,共7页
In this paper, Xinjiang's coal field is selected as the investigation area. Through a series of field surveys in Xinjiang, we made the small-scale area analysis of coal field fire using the ground remote sensing tech... In this paper, Xinjiang's coal field is selected as the investigation area. Through a series of field surveys in Xinjiang, we made the small-scale area analysis of coal field fire using the ground remote sensing technique, and presented the reasonable evaluation of thermal anomaly conditions of Xinjiang's coal field arising from coal self-ignition fires. The results show that the method of small-scale area analysis is available for examining the extinguished actuality of coal fires and detecting fire spots. Therefore, for the selected fire-extlngulshed coal field in Xinjiang, the fire extinguishing effect was effectively analyzed by the means, and the new hidden thermal dangers were sought and diagnosed. For the coal field where the fire has not been extinguished, the utilization of this means approximately identified the severity and range of the fire area, and provided the quantitative and ground references for extinguish engineering. 展开更多
关键词 coal field fire thermal anomaly remote sensing SMALL-SCALE
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Research and application of strip mining of village coal pillar at coal field of the north of the Yellow River in Shandong Province
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作者 XU Nai-zhong TIAN Jin-zhou GAO Chao 《Journal of Coal Science & Engineering(China)》 2012年第3期232-237,共6页
This paper focuses on the village coal pillar under huge thick loose bed and thin bedrock over high prelatic water level at the north of the Yellow River. The strip mining technology was used to protect the village ho... This paper focuses on the village coal pillar under huge thick loose bed and thin bedrock over high prelatic water level at the north of the Yellow River. The strip mining technology was used to protect the village houses. The stratum structure control action of mining subsidence was used to design the mining and pillar width. To further raise resources recovery, we adopted the mutative scheme of mining and pillar width. Observation was carried out while mining. Research shows there is feasibility of the strip mining technology to protecting the village buildings of the village coal pillar under huge thick loose bed and thin bedrock over high prelatic water level at the north of the Yellow River. Finally, subsidence parameters of strip mining were obtained. It is the basic data of the strip mining of the coal field at the north of the Yellow River. 展开更多
关键词 huge thick loose bed thin bedrock high prelatic water level strip mining coal field Yellow River
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THE REMOTE SENSING IN COAL GEOLOGY——A study on detection of coal spontanous burning by remote sensing in the coal fields in the north of China
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作者 Guan Haiyan(China Coal Remote Sensing Geology Centre) 《遥感信息》 CSCD 1990年第A02期3-4,共2页
The spontaneous burning has been lasting for thousands of years in the coal fields in the north of China. It spreads from the west (Tianshan coal field) to the east (Huolinhe coal field). Its E-W extension is up to 37... The spontaneous burning has been lasting for thousands of years in the coal fields in the north of China. It spreads from the west (Tianshan coal field) to the east (Huolinhe coal field). Its E-W extension is up to 3750km, concentrating in N35°toN45°, its vertical depth up to 260m, and the surface temprature locally up to 270℃. Annually, it burns out 0, 250-300 million tones of coal, causing economic loss equivalent to 2-3 billion R.M.B. Yuan.It destroies coal resources and causes hazards in coal mines. In order to locate the extent and the direction in coal burning areas, the remote sensing technique has heen used and has produced an obvious benefit. 展开更多
关键词 THE REMOTE SENSING IN coal GEOLOGY A study on detection of coal spontanous burning by remote sensing in the coal fields in the north of China
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Research of CAN Bus in the Coal Mine Field Data Transmission based on Reliability
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作者 LUO Li 《International Journal of Technology Management》 2014年第8期83-85,共3页
Under the current situation, China' s rapid economic development, various new science, emerge in an endless stream of new technology, under the environment of coal mine industry, seize the opportunity, by virtue of i... Under the current situation, China' s rapid economic development, various new science, emerge in an endless stream of new technology, under the environment of coal mine industry, seize the opportunity, by virtue of its original advantages, coupled with technology introduction and innovation consciousness of the play, ushered in a new period of development, into the modern coal mining era. CAN bus technology is a new technology which has the typical data transmission in coal mining, the introduction of a certain degree of CAN bus technology, not only improve the efficiency of data transmission, at the same time, in terms of reliability and greatly enhance. In this paper, to a certain extent on the introduction of the CAN bus technology, and on this basis, based on the CAN bus in the coal mine field data transmission reliability research and analysis 展开更多
关键词 CAN Bus Underground coal Mines field Bus Control System Data Transmission Reliability
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Geochemical and Mineralogical Characteristics of Pleistocene Lignites and Associated Sediments of Marathousa Coal Field,Central Peloponnese,Greece
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作者 A.E.KELEPERTSIS E.KONTIS 《Chinese Journal Of Geochemistry》 EI CAS 1997年第1期8-19,共12页
The mineralogy and geochemistry data are presented for thirty-seven shales, four concretions, two carbonate sediments and seven lignites from the Marathousa coal field of the Megalopolis Basin in Greece. The argillace... The mineralogy and geochemistry data are presented for thirty-seven shales, four concretions, two carbonate sediments and seven lignites from the Marathousa coal field of the Megalopolis Basin in Greece. The argillaceous rocks consist of chlorite, illite, kaolinite, albite,quartz, opal-A, calcite and dolomite; the concretions of aragonite, gypsum and pyrite; and the carbonate rocks of calcite, quartz and illite. The mineral matter in the lignites consists of gyp-sum, quartz, albite, chlorite, illite, opal-A, dolomite, pyrite, and rarely calcite and kaolinite.A three-factor model explains the total variation of major and trace elements in the argillaceous sediments. The first factor is an aluminosilicate factor and involves the following elements: Al,Si, Mg, Na, K, Ti, Mn, Nb, Y, Rb, Zn, Cu, Ni, Cr, Nd and V, associated with chlorite,albite and illite. The second factor involves the elements Ca, Sr, Ba, Zn and Sc and is related to carbonate lithology and mainly the carbonate concretions with gypsum. The third factor in-volves Fe and Ce with a weak association with Mn. The diagenesis of the Marathousa sedi-ments and lignites was ot very advanced as indicated by (a) the total thickness of the sequence (500 m), (b) the presence of biogenic silica (opal-A) and (c) the age of the deposit (Pleis-tocene). For these reasons the presence of chlorite, illite and kaolinite in the sediments and lig-nite is due not to diagenetic reactions but to weathering of the flysch and metamorphic rocks at the edges of the Megalopolis Basin and transport of the weathering products (illite, chlorite,kaolinite) into the basin of deposition. The diagenetic minerals of the Marathousa sequence in-clude pyrite, gypsum, dolomite and aragonite. 展开更多
关键词 地球化学 矿物学 褐煤 煤田 希腊 沉积作用 更新世
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