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Analysis and Design Innovation on Underground Gasifier for Medium-Deep Coal Seam 预览
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作者 Kong Lingfeng Zhan Enqiang Zhao Chenhui 《中国油气:英文版》 CAS 2019年第4期32-37,共6页
Over the past 80 years,dozens of underground coal gasification(UCG)mine field tests have been carried out around the world.However,in the early days,only a small number of shallow UCG projects in the former Soviet Uni... Over the past 80 years,dozens of underground coal gasification(UCG)mine field tests have been carried out around the world.However,in the early days,only a small number of shallow UCG projects in the former Soviet Union achieved commercialised production.In this century,a few pilot projects in Australia also achieved short-term small-scale commercialised production using modern UCG technology.However,the commercialisation of UCG,especially medium-deep UCG projects with good development prospects but difficult underground engineering conditions,has not progressed smoothly around the world.Considering investment economy,a single gasifier must realise a high daily output and accumulated output,as well as hold a long gasification tunnel to control a large number of coal resources.However,a long gasification tunnel can easily be affected by blockages and failure,for which the remedial solutions are difficult and expensive,which greatly restricts the investment economy.The design of the underground gasifier determines the success or failure of UCG projects,and it also requires the related petroleum engineering technology.Combining the advantages of the linear horizontal well(L-CRIP)and parallel horizontal well(P-CRIP),this paper proposes a new design scheme for an“inclined ladder”underground gasifier.That is to say,the combination of the main shaft of paired P-CRIP and multiple branch horizontal well gasification tunnels is adopted to realise the control of a large number of coal resources in a single gasifier.The completion of the main shaft by well cementation is beneficial for maintaining the integrity of the main shaft and the stability of the main structure.The branch horizontal well is used as the gasification tunnel,but the length and number of retracting injection points are limited,effectively reducing the probability of blockage or failure.The branch horizontal well spacing can be adjusted flexibly to avoid minor faults and large cracks,which is conducive to increasing the resource utilisation rate.In add 展开更多
关键词 UNDERGROUND COAL Gasification(UCG) Medium-deep COAL Seam Controlled Retracting Injection Point(CRIP) Parallel HORIZONTAL WELL Pair Branch HORIZONTAL WELL “Inclined Ladder”Underground GASIFIER Cluster Coiled Tubing Flexible and Combustible Tubing GASIFICATION Tunnel GASIFICATION Chamber Coal-based Syngas
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将退役闲置矿山巷道改建为大型地下储备油库的探讨 预览
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作者 杨志泉 张振 尹华雷 《石油库与加油站》 2019年第4期1-4,I0001共5页
简要叙述了建立石油资源储备的重要性、石油储备的主要方式和地下储备的优越性,探讨并提出了利用退役闲置矿山巷道改建为大型地下储备油库的设想和初步方案,其隐蔽性强,安全性高;储量大,不占地;建设成本低,工期短;设备投资少;运行管理... 简要叙述了建立石油资源储备的重要性、石油储备的主要方式和地下储备的优越性,探讨并提出了利用退役闲置矿山巷道改建为大型地下储备油库的设想和初步方案,其隐蔽性强,安全性高;储量大,不占地;建设成本低,工期短;设备投资少;运行管理费用低等,建议国家有关部门加紧研究实施。 展开更多
关键词 闲置 矿山 巷道 改建 地下 储备 油库 探讨
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A O-dimensional cavity growth submodel for use in reactor models of underground coal gasification 预览
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作者 Greg Perkins 《国际煤炭科学技术学报:英文版》 2019年第3期334-353,共20页
Modelling of the underground coal gasification process is dependent upon a range of sub-models. One of the most important is the calculation of the cavity growth rate as a function of various operating conditions and ... Modelling of the underground coal gasification process is dependent upon a range of sub-models. One of the most important is the calculation of the cavity growth rate as a function of various operating conditions and coal properties. While detailed 1-dimensional models of coal block gasification are available, it is not easy to couple them directly with reactor models, which aim to simulate the complete process. In this paper, a O-dimensional cavity growth sub-model is presented. The model is based on the concept of a surface reaction and incorporates physics to account for moisture evaporation, water influx, coal pyrolysis, coal thermo-mechanical fragmentation and the build up of an ash layer on the char. The model is validated using measurements from laboratory experiments on coal cores and coal blocks. A comparison of calculated results from several UCG field trials shows that the model can provide good estimates of cavity growth rate for reasonable input parameters. Finally, simulation results of cavity growth in the combustion and gasification zones as a function of the bulk gas temperature, gas pressure, water influx rate, ash layer thickness and coal fragmentation behaviour are presented. 展开更多
关键词 UNDERGROUND COAL GASIFICATION CAVITY growth Chemical REACTION
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Is China’s Economy Overestimated?*——Counter-Evidence from the Underground Economy 预览
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作者 王永兴 《中国经济学人:英文版》 2019年第3期30-43,共14页
Over the past four decades of reform and opening up since 1978, China’s GDP has been growing at 9.5% on an annual average basis. While some scholars believe that China’s economic growth is systematically overestimat... Over the past four decades of reform and opening up since 1978, China’s GDP has been growing at 9.5% on an annual average basis. While some scholars believe that China’s economic growth is systematically overestimated, this paper carries out an estimation of China’s underground economy and finds that due to the existence of the underground economy, China’s real GDP is systematically underestimated. China’s official GDP statistics generally reflect a real picture of its economic growth. The size of China’s underground economy is significantly influenced by total electricity consumption, the selfemployed ratio, labor participation rate and money supply. These findings are of great significance for policy-making. 展开更多
关键词 underground economy LATENT variable CASH ratio MODEL MULTIPLE indicators MULTIPLE causes (MIMIC) MODEL
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基于案例的地下污水处理厂技术经济分析 预览
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作者 郑永鹏 《城市道桥与防洪》 2019年第7期328-331,M0033共5页
近年来,地下污水处理厂在全国得到了极大的推广。现从造价角度总结了地下污水处理厂的技术经济特点,通过湖南省岳阳市某地下污水处理厂的建设投资,分析了地下污水处理厂的技术经济指标。
关键词 地下 污水处理厂 技术经济 工程实例
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新型地下管廊施工工艺研究
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作者 钱瑞雪 陈新元 刘琥铖 《施工技术》 CAS 2019年第10期104-107,共4页
针对传统管廊施工拆装量大、效率低、安全隐患较大和施工质量不稳定的情况,设计了一种快速支模、拆模和移动的智能台车。从台车设计要求、结构设计和工作原理分析、结构的理论分析和控制系统设计几个方面阐述台车研发过程。利用有限元软... 针对传统管廊施工拆装量大、效率低、安全隐患较大和施工质量不稳定的情况,设计了一种快速支模、拆模和移动的智能台车。从台车设计要求、结构设计和工作原理分析、结构的理论分析和控制系统设计几个方面阐述台车研发过程。利用有限元软件ANSYS Workbench对台车结构进行分析校核,现场施工应用验证台车设计可行性。通过与传统施工工艺进行对比,介绍了智能模板台车浇筑的优势。 展开更多
关键词 地下工程 管廊 台车 有限元分析 施工技术
富水砂卵石地层中常压开仓加固技术 预览
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作者 韩亮 《现代城市轨道交通》 2019年第3期55-58,共4页
地铁盾构施工过程中,因设备故障必须开仓处理时受到诸多不利因素的影响,特别是在不具备带压进仓富水砂卵石地层的条件下,只能从地面进行地层加固处理来达到设备检修或进仓条件。以某市地铁盾构区间盾构机因中心回转体脱落造成隧道涌水... 地铁盾构施工过程中,因设备故障必须开仓处理时受到诸多不利因素的影响,特别是在不具备带压进仓富水砂卵石地层的条件下,只能从地面进行地层加固处理来达到设备检修或进仓条件。以某市地铁盾构区间盾构机因中心回转体脱落造成隧道涌水涌砂事故为背景,研究采取地面三轴搅拌桩加固、化学注浆止水、降水等技术措施,在常压进仓作业条件下顺利完成了设备检修,解决了富水砂卵石地质条件下不能常压开仓的技术难题。 展开更多
关键词 地铁 富水砂卵石地层 盾构施工 地层加固 带压开仓
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论新时代我国城市地下空间高质量开发和可持续利用 被引量:2
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作者 王成善 周成虎 +6 位作者 彭建兵 樊杰 朱合华 李晓昭 程光华 戴春森 徐能雄 《地学前缘》 EI CAS CSCD 北大核心 2019年第3期1-8,共8页
开发利用城市地下空间,开辟城镇化发展新资源,是解决城市病、改善城市生态环境、优化城市空间结构、提高城市韧性的重要途径。本文深入分析了新时代中国城市地下空间开发利用的现状,认为存在冒进式开发与总体供给不足、碎片化利用与协... 开发利用城市地下空间,开辟城镇化发展新资源,是解决城市病、改善城市生态环境、优化城市空间结构、提高城市韧性的重要途径。本文深入分析了新时代中国城市地下空间开发利用的现状,认为存在冒进式开发与总体供给不足、碎片化利用与协同规划缺位、被动式应对与科技支撑薄弱、无序化管理与法律法规匮乏等若干紧迫问题,明确了'立法为本、规划引领、调查先行、管理智能、科研支撑'的开发利用原则,提出了全面开展城市地下空间调查评价、尽快建立地下空间协同规划体系、加速构建地下空间智慧管理体系、超前布局地下空间科技发展战略、尽早健全城市地下空间法律法规等五个方面的具体对策建议,充分利用中国体制上的优势,集成国际城市地下空间开发利用先进的理念和技术,从而推动我国新时代城市地下空间产业快速发展、科技水平不断提高和地下空间体系日趋完善,在全球树立城市地下空间资源可持续开发利用的典范。 展开更多
关键词 地下空间 开发 利用 城市
Roles of Fenlong Technology in the Increase of Grain Yield and Construction of a Huge"Underground Reservoir" 预览
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作者 Benhui WEI 《农业生物技术:英文版》 CAS 2019年第1期206-208,共3页
Fenlong farming technology was introduced.It has characteristics of very deep tillage and evenly smashing soil,and can evenly smash soil without disturbing soil layers to complete the task of soil preparation.It can b... Fenlong farming technology was introduced.It has characteristics of very deep tillage and evenly smashing soil,and can evenly smash soil without disturbing soil layers to complete the task of soil preparation.It can be widely used in cultivated land,saline-alkali land,lime concretion black soil,degraded grassland,etc.After the application of the technology in 34 crops in 24 provinces,it can increase yield by 10%-50%and improve quality by above 5%.Fenlong technology can increase soil reservoir capacity,enhance the infiltration rate of rainwater in soil and make"surplus"effect obvious.If the country plans and promotes the technology in 160 million hm 2 of land(including 67 million hm 2 of cultivated land,20 million hm 2 of saline-alkali land,6.7 million hm 2 of marginal land and 67 million hm 2 of degraded grassland),the total volume of loosened soil in arable land will increase from 198.1 billion to 840.0 billion m 3,and the capacity of a"underground reservoir"will increase by 675 million m 3,while natural precipitation reserves will increase by 162 billion m 3.It can effectively solve food security problems and water resource problems such as drought,floods,and industrial,agricultural and domestic water shortages,as well as serious disaster hazards caused by groundwater that has been evacuated in China. 展开更多
关键词 Fenlong FARMING Yield INCREASE and quality improvement UNDERGROUND RESERVOIR Deep problems China
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Quantifying the thermal damping effect in underground vertical shafts using the nonlinear autoregressive with external input(NARX)algorithm 预览
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作者 Pedram Roghanchi Karoly C.Kocsis 《矿业科学技术学报:英文版》 CSCD 2019年第2期255-262,共8页
As air descends the intake shaft,its infrastructure,lining and the strata will emit heat during the night when the intake air is cool and,on the contrary,will absorb heat during the day when the temperature of the air... As air descends the intake shaft,its infrastructure,lining and the strata will emit heat during the night when the intake air is cool and,on the contrary,will absorb heat during the day when the temperature of the air becomes greater than that of the strata.This cyclic phenomenon,also known as the “thermal damping effect”will continue throughout the year reducing the effect of surface air temperature variation.The objective of this paper is to quantify the thermal damping effect in vertical underground airways.A nonlinear autoregressive time series with external input(NARX)algorithm was used as a novel method to predict the dry-bulb temperature(Td)at the bottom of intake shafts as a function of surface air temperature.Analyses demonstrated that the artificial neural network(ANN)model could accurately predict the temperature at the bottom of a shaft.Furthermore,an attempt was made to quantify typical “damping coefficient”for both production and ventilation shafts through simple linear regression models.Comparisons between the collected climatic data and the regression-based predictions show that a simple linear regression model provides an acceptable accuracy when predicting the Td at the bottom of intake shafts. 展开更多
关键词 UNDERGROUND mining Vertical openings THERMAL damping effect Artificial neural network NONLINEAR AUTOREGRESSIVE with EXTERNAL input(NARX)
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Towards Understanding the Security of Modern Image Captchas and Underground Captcha-Solving Services
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作者 Haiqin Weng Binbin Zhao +4 位作者 Shouling Ji Jianhai Chen Ting Wang Qinming He Raheem Beyah 《大数据挖掘与分析(英文)》 2019年第2期118-144,共27页
Image captchas have recently become very popular and are widely deployed across the Internet to defend against abusive programs. However, the ever-advancing capabilities of computer vision have gradually diminished th... Image captchas have recently become very popular and are widely deployed across the Internet to defend against abusive programs. However, the ever-advancing capabilities of computer vision have gradually diminished the security of image captchas and made them vulnerable to attack. In this paper, we first classify the currently popular image captchas into three categories: selection-based captchas, slide-based captchas, and click-based captchas. Second, we propose simple yet powerful attack frameworks against each of these categories of image captchas. Third, we systematically evaluate our attack frameworks against 10 popular real-world image captchas,including captchas from tencent.com, google.com, and 12306.cn. Fourth, we compare our attacks against nine online image recognition services and against human labors from eight underground captcha-solving services. Our evaluation results show that(1) each of the popular image captchas that we study is vulnerable to our attacks;(2) our attacks yield the highest captcha-breaking success rate compared with state-of-the-art methods in almost all scenarios;and(3) our attacks achieve almost as high a success rate as human labor while being much faster.Based on our evaluation, we identify some design flaws in these popular schemes, along with some best practices and design principles for more secure captchas. We also examine the underground market for captcha-solving services, identifying 152 such services. We then seek to measure this underground market with data from these services. Our findings shed light on understanding the scale, impact, and commercial landscape of the underground market for captcha solving. 展开更多
关键词 IMAGE captchas CAPTCHA SECURITY captcha-solving service UNDERGROUND market
大型地下综合交通枢纽一体化设计研究 预览
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作者 马瑾 《华中建筑》 2019年第6期77-80,共4页
该文从大型综合交通枢纽一体化规划设计的内涵出发,阐述了首批建设的新型交通枢纽一体化设计中存在的问题。结合于家堡站综合交通枢纽的实际建设情况,提出了枢纽一体化建设的模式和实际规划设计情况。对一体化交通系统、一体化综合开发... 该文从大型综合交通枢纽一体化规划设计的内涵出发,阐述了首批建设的新型交通枢纽一体化设计中存在的问题。结合于家堡站综合交通枢纽的实际建设情况,提出了枢纽一体化建设的模式和实际规划设计情况。对一体化交通系统、一体化综合开发及城市空间融合等进行了论述,为类似工程设计提供借鉴。 展开更多
关键词 交通枢纽 一体化设计 地下 空间
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TrtApplication of advanced water exploration technology in an iron mine roadway 预览
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作者 Shuhan Hu 《探索-地质与矿业研究》 2019年第1期26-27,共2页
TRTAdvanced geological exploration is a relatively advanced Prediction Technology in Mine Roadway Construction.,It has been widely used in mine construction..The hydrogeological conditions of an iron mine are complex.... TRTAdvanced geological exploration is a relatively advanced Prediction Technology in Mine Roadway Construction.,It has been widely used in mine construction..The hydrogeological conditions of an iron mine are complex.,Mine water inflow is larger,Outburst during Roadway Excavation,Water gushing phenomenon is frequent,Poor stability of surrounding rock.To this end,AdoptedTrtCarry out multiple detection experiments with advanced detection technology,For roadway geological advance detection.Combined with drilling engineering verification, TRTAdvanced detection technology can provide reliable advanced Prediction,Provide reliable geological information in time,It provides an important guarantee for the safety of underground roadway excavation. 展开更多
关键词 TRTTechnology GEOLOGICAL Prediction UNDERGROUND ROADWAY ADVANCE water EXPLORATION TOMOGRAPHY
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井下爆炸材料库底鼓破坏特征及控制研究 预览
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作者 潘先峰 《煤矿爆破》 2019年第3期11-14,共4页
为解决井下爆炸材料库巷道底鼓问题,以安徽省某井下爆炸材料库巷道为研究对象,介绍了井下爆炸材料库巷道变形特征,对巷道的变形破坏的影响因素进行了分析。笔者结合现场实际,提出巷道拱顶板和巷道两帮采用"锚网索喷+梯形钢带组合&q... 为解决井下爆炸材料库巷道底鼓问题,以安徽省某井下爆炸材料库巷道为研究对象,介绍了井下爆炸材料库巷道变形特征,对巷道的变形破坏的影响因素进行了分析。笔者结合现场实际,提出巷道拱顶板和巷道两帮采用"锚网索喷+梯形钢带组合"支护、巷道底板采用"锚杆+混凝土反拱组合结构"的新支护形式,并将控制方法和支护方案进行了工程实际应用,旨在为类似条件的井下爆炸材料库设计及其他类似巷道工程施工提供参考。 展开更多
关键词 井下 爆炸材料库 底鼓 破坏特征 控制 支护
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Study on Characteristics of Underground Horizontal Electric Field Caused by Lightning Return Stroke Based on FDTD Method 预览
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作者 Zhao Liang Gu Lili +1 位作者 Hao Ling Liu Ruixiang 《气象与环境研究:英文版》 CAS 2019年第1期39-42,共4页
Based on the MTLL lightning return stroke model, a two-dimensional cylindrical finite-difference time-domain (FDTD) model for underground horizontal electric field was established, and the effects of distance from lig... Based on the MTLL lightning return stroke model, a two-dimensional cylindrical finite-difference time-domain (FDTD) model for underground horizontal electric field was established, and the effects of distance from lightning channel, depth, soil electrical conductivity and its distribution, and return stroke current on the characteristics of underground horizontal electric field were analyzed. The results showed that as long as the electrical conductivity of soil existed, the peak of underground horizontal electric field decreased with the increase in the horizontal distance from lightning channel. When the electrical conductivity of the upper soil was much smaller than that of the lower soil, the peak of corresponding horizontal electric field was larger than the electric field peak as the electrical conductivity of the upper soil was larger than that of the lower soil. When the electrical conductivity of the upper soil was less than that of the lower soil, the growth and decay of the horizontal electric field were faster than the growth and decay as the electrical conductivity of the upper soil was larger than that of the lower soil. 展开更多
关键词 UNDERGROUND HORIZONTAL electric field LIGHTNING RETURN stroke FDTD Single layer soil LAYERED
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煤矿井下传感器老化测试方法探讨 预览
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作者 宋凯敏 《煤矿现代化》 2019年第2期169-171,共3页
煤矿井下传感器种类繁多,对保证煤炭安全顺利开采意义重大。但由于井下环境恶劣,传感器在井下经长期使用后容易受水汽、温度、粉尘等因素影响,会出现监测精度差、稳定性异常等问题,这是典型的老化现象,会给井下的正常工作带来困扰。本... 煤矿井下传感器种类繁多,对保证煤炭安全顺利开采意义重大。但由于井下环境恶劣,传感器在井下经长期使用后容易受水汽、温度、粉尘等因素影响,会出现监测精度差、稳定性异常等问题,这是典型的老化现象,会给井下的正常工作带来困扰。本文以潞安集团郭庄煤矿为实例,首先介绍了传感器老化测试装置的建立,然后对传感器老化的测试流程进行了详细分析,通过老化测试可以将有缺陷传感器筛选出来,保证井下传感器正常可靠,为井下开采工作保驾护航。 展开更多
关键词 井下 传感器 老化 监测 监控 升级
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Underground coal gasification and its strategic significance to the development of natural gas industry in China 预览
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作者 ZOU Caineng CHEN Yanpeng +3 位作者 KONG Lingfeng SUN Fenjin CHEN Shanshan DONG Zhen 《石油勘探与开发:英文版》 2019年第2期205-215,共11页
Based on the present situation and trend of underground coal gasification in China and overseas, this article puts forward the basic concept, mechanism and mode of underground coal gasification, and presents the chall... Based on the present situation and trend of underground coal gasification in China and overseas, this article puts forward the basic concept, mechanism and mode of underground coal gasification, and presents the challenges, development potential and development path now faced. In China, underground coal gasification which is in accord with the clean utilization of coal can produce "artificial gas", which provides a new strategic approach to supply methane and hydrogen with Chinese characteristics before new energy sources offer large-scale supply. Coal measure strata in oil-bearing basins are developed in China, with 3.77 trillion tons coal reserves for the buried depth of 1000-3 000 m. It is initially expected that the amount of natural gas resources from underground coal gasification to be 272-332 trillion cubic meters, which are about triple the sum of conventional natural gas, or equivalent to the total unconventional natural gas resources. According to the differences of coal reaction mechanism and product composition of underground coal gasification, the underground coal gasification can be divided into three development modes, hydrogen-rich in shallow, methane-rich in medium and deep,supercritical hydrogen-rich in deep. Beyond the scope of underground mining of coal enterprises, petroleum and petrochemical enterprises can take their own integration advantages of technologies, pipeline, market and so on, to develop underground coal gasification business based on their different needs and technical maturity, to effectively exploit a large amount of coal resources cleanly and to alleviate the tight supply of natural gas. It can also be combined with using the produced hydrogen in nearby area and the CO2 flooding and storage in adjacent oil areas to create a demonstration zone for net zero emissions of petroleum and petrochemical recycling economy. It is significant for reserving resources and technologies for the coming "hydrogen economy" era, and opening up a new path for China’s "clean, low carbon, safe a 展开更多
关键词 COAL underground COAL GASIFICATION natural GAS GAS revolution coal-made methane coal-made hydrogen SUPERCRITICAL WATER SUPERCRITICAL WATER GASIFICATION
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Optimizing dewatering design for a metro station on the Chengdu Metro Line 7 预览
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作者 LI Ke KANG Xiao-bing 《地下水科学与工程:英文版》 2019年第2期155-164,共10页
At present, most calculation results regarding foundation pit dewatering are ideal values, making construction resources prone to being wasted. In order to optimize the traditional pipe well design of large wells, the... At present, most calculation results regarding foundation pit dewatering are ideal values, making construction resources prone to being wasted. In order to optimize the traditional pipe well design of large wells, the linear programming solution module in Excel is used, with the total water inflow taken as the objective function, the water level drawdown used as the constraint and test condition, and a station project on the Chengdu Metro Line 7 serving as the subject of this study. The total water inflow of the traditional pipe well design is optimized by the simplex method, producing a total water inflow of 4 040.65 m^3/d, which, compared with 4 829.79 m^3/d, the total water inflow calculated by means of the traditional design optimization method, engenders a reduction of roughly 16% per day. The feasibility of the optimization methodology is verified by the drawdown constraint, which reveals the decrease of construction costs and the diminution of the influence that the lowered groundwater level has on the surroundings of the metro station. Finally, references are provided as to optimizing the dewatering designs for other metro stations in similar engineering and hydrogeological conditions. 展开更多
关键词 UNDERGROUND SPACE Objective function DEWATERING design optimization PROGRAMMING SOLVER
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The creep compaction behavior of crushed mudstones under the step loading in underground mining 预览
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作者 Zhibiao Guo Qiong Wang +4 位作者 Songyang Yin Xiaohui Kuai Dongshan Yan Mengyi Li Yandong Qu 《国际煤炭科学技术学报:英文版》 2019年第3期408-418,共11页
The crushed rocks are used as a filling material in mined丒out areas of underground mining. Compared with the man-made filling materials, the crushed rocks exhibit higher compressibility and lower stability, which may... The crushed rocks are used as a filling material in mined丒out areas of underground mining. Compared with the man-made filling materials, the crushed rocks exhibit higher compressibility and lower stability, which may result in instability of surrounding rock and surface subsidence. To study the creep compaction behavior of crushed mudstones, a series of creep tests are conducted. The investigations show that the creep compaction behavior of crushed mudstones is highly dependent on the original grain composition and axial stress applied on the samples. The samples with more large particles are easier to deform at initial loading stage for more large voids existed in the samples, and exhibit greater stability than those with smaller particles when the axial stress less than the bearing capacity of uframework structure When the axial stress is higher than 20 MPa, the influences of grain composition on deformability of crushed mudstones are weakened after the samples experience repeated compression. At lower stress level, the creep behavior prefers to occur in the samples w.h smaller particles, which is mainly caused by particles flow without significant particle breakage. As the axial stress increases, the single-sized sample with smaller particle size and the well-graded sample with larger Talbol power exponent n present more unstable under the constant stress. In addition, the filling of the residual intergranular voids by small particles formed by crushing and splitting behavior is the main cause of creep deformation. Lastly, a creep equation of crushed mudstones is obtained in this paper, which can agree with the experimental results in good. 展开更多
关键词 CRUSHED MUDSTONES Grain composition CREEP COMPACTION BEHAVIOR UNDERGROUND mining
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马兰矿井下无人值守变电所电力监控系统技术研究 预览 被引量:1
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作者 武艳红 《现代矿业》 CAS 2019年第3期158-160,共3页
为了探讨井下无人值守变电所的电力监控系统技术,以西山煤电马兰矿为背景,详细阐述了井下无人值守变电所电力监控系统技术的各项基本参数,如额定工作电压及整机输入视在功率、交换机或监控分站的传输口、高压配电装置的传输口、真空馈... 为了探讨井下无人值守变电所的电力监控系统技术,以西山煤电马兰矿为背景,详细阐述了井下无人值守变电所电力监控系统技术的各项基本参数,如额定工作电压及整机输入视在功率、交换机或监控分站的传输口、高压配电装置的传输口、真空馈电开关的传输口、RS485光信号传输口、报警声强、视频信号输入口、后备电池参数、模拟量传输处理误差等。研究表明,该系统为井下供电系统提供了各种保护监视和控制功能,并且通过可靠的通讯信号传输到地面调度中心,使值班人员对井下电网运行情况有详细的了解,该系统在马兰矿运行效果良好,有效保证井下供电系统的供电安全和供电可靠性,并且为马兰矿带来了较高的经济效益和很好的社会效益,该系统具有非常广阔的应用前景。 展开更多
关键词 井下 无人值守变电所 电力自动化 监控系统
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