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991.
李鹏  王先科 《中州煤炭》2022,(9):276-278
为了方便煤炭的运输,某矿使用了矿用履带式搬运车。履带运输车解决了轮式运输车在恶劣道路条件下不能行走的问题,这种履带车是一种新型的运输工具,其特点是体积小、转弯灵活、动力强大,可在不受场地限制的情况下轻松通过狭窄的地方,能有效解决山区、土壤、陡坡等恶劣条件下物料的运输问题,适合普通运输车辆无法通行的地方。介绍了矿用履带式搬运车的主要结构以及工作原理,并给出了实际应用中应注意的事项。  相似文献   
992.
中国煤矿井下地应力数据库及地应力分布规律   总被引:3,自引:0,他引:3       下载免费PDF全文
收集了采用井下小孔径水压致裂地应力测量装置获得的煤矿地应力数据,以及其他采用应力解除法、水压致裂法等获得的煤矿地应力数据,共计1 357条。在此基础上建立了“中国煤矿井下地应力数据库”,绘制了中国煤矿矿区地应力分布图。分析了我国煤矿井下地应力分布特征和主要影响因素,取得以下研究成果:① 埋深是影响煤矿井下地应力的重要因素。垂直应力总体上随埋深增加不断增大,但数据存在一定的离散性。最大、最小水平主应力总体上也与埋深呈正相关关系,但数据离散性更大。② 在浅部煤矿,地应力类型主要为逆断型应力状态(σH>σh>σV);在千米深井,主要为正断型应力状态(σV>σH>σh);介于两者之间主要为走滑型应力状态(σH>σV>σh)。③ 水平应力与垂直应力的比值(包括最大、最小水平主应力与垂直应力的比值;平均水平主应力与垂直应力的比值;最大水平主应力与最小水平主应力之差与垂直应力的比值),埋深越小,这些比值离散性越大,分布范围越广。随着埋深增加,比值的离散性和范围越来越小,并逐渐趋于某一定值。④ 粉砂岩、细砂岩、泥质砂岩和泥岩4类岩性地应力数据统计结果表明,总体上,岩石强度越高,承受的水平应力越大。⑤ 弹性模量较大的岩石,水平应力较高;弹性模量较低的松软破碎岩层,水平应力较低。  相似文献   
993.
Energy is one of the indispensable factors regarding the economic development of Turkey. Examination of calorific values in coal deposits has importance in the production of energy, and thus planning of the coal deposit. In this article, multivariate statistical analysis techniques, including cluster analysis and discriminant analysis, were applied to calorific values obtained from boreholes. Cluster analysis grouped borehole locations into two clusters based on the similarity of calorific values. Afterwards, discriminant functions were supported to cluster analysis and developed a linear discriminant function. Based on the locations of the boreholes, it was concluded that calorific values are a highly central part of the coal deposit. Thus, this article shows the usefulness of multivariate statistical analysis techniques for understanding spatial variation of coal deposits and effective deposit management.  相似文献   
994.
Effect of pine sawdust on the removal of arsenic and sulfur during Shanxi Tuanbo-2 coal pyrolysis was investigated. Results showed that adding pine sawdust could increase the removals of arsenic and sulfur during Shanxi Tuanbo-2 coal pyrolysis, and when the ratio of the pine sawdust was 50%, the arsenic removal was the highest; at this ratio, the total sulfur removal also was the highest. Adding pine sawdust also increased pyritic sulfur and organic sulfur removal. Furthermore, results also indicated that adding pine sawdust made arsenic associated with sulfates and monosulfides and arsenic in stable forms escape more easily.  相似文献   
995.
焦化副产品价值与副产品热值间存在线性关系,可以通过建立炼焦煤性质与副产品热值的关系推测出每种炼焦煤的副产品价值和炼焦煤的净价格(煤炭价格—副产品价格)。这种炼焦煤副产品价值预测方法在实际优化配煤成本时可以综合考虑炼焦煤的价值,有助于选择净价格更低的炼焦煤。  相似文献   
996.
Experimental results for methane and carbon dioxide diffusion in coal, as reported in the literature, often lead to diffusion rates of CO2 appearing to be much greater than that of CH4. The interpretation sometimes offered that the diffusion coefficient for CO2 is 1–2 orders of magnitude higher than that of CH4, violates fundamental principles. Nevertheless, the experimental observations require explanation. In this article, we: (a) Develop simplified models for the fast estimation of transport coefficients. These are compared with comprehensive grand canonical Monte Carlo (GCMC) and molecular dynamic (MD) simulations, collectively defined as molecular simulations (MS), which provide theoretical adsorption isotherms and various transport coefficients based on multicenter potential energy equations. The simplified models are shown to have acceptable accuracies. (b) Use the simplified models to compare diffusivities of CO2 and CH4 in carbon nanopores. For all cases examined, the diffusivity of CH4 is always larger than that of CO2. (c) Offer two explanations for the apparently contradictory experimental observations (that CO2 sometimes appears to diffuse much faster than the CH4 molecule, even though CH4 is lighter and has smaller adsorption affinity): (i) CH4 mobility could be significantly reduced by directional forces resulting from irregular pore geometries; and (ii) if pores contain throats with sizes close to the CH4 molecular diameter, the energy barrier that the methane molecules must overcome to proceed through is much larger than that required for CO2. (d) Demonstrate that both mobility and connectivity issues can be addressed using kinetic theory in association with percolation analysis. Furthermore, this method of understanding pore networks provides a number of important quantitative measures including percolation threshold, size of largest cluster, shortest path and tortuosity. Separating different transport mechanisms, as we propose here, provides improved insights into the complex transport phenomena that occur in carbonaceous porous media. In many cases, diffusivities reported in the literature with mixed mechanisms are better named “apparent transport coefficients,” because they lump in other unrelated phenomena, violating the fundamental basis of, or mathematical assumptions imposed on, the definition of diffusion. © 2011 American Institute of Chemical Engineers AIChE J, 2012  相似文献   
997.
The front abutment pressure of a fully-mechanized workface of 11061 soft coal isolated island of Liangbei Coal Mine was measured and studied using a self-developed mining-induced stress monitoring syst...  相似文献   
998.
为准确测定煤及粉煤灰中伴生锂元素,采用高温灰化、硝酸-氢氟酸-高氯酸三元体系消解,电感耦合等离子体发射光谱(ICP-OES)法测定煤及粉煤灰中伴生锂元素。结果表明,通过对灰样分解方法、射频功率、观测高度、分析谱线和观测方式的优选,无需基体匹配,即可实现煤和粉煤灰中伴生锂元素的测定。该方法的煤及粉煤灰中锂的检出限分别为0.01、0.03μg/g,锂含量差异较大的3个煤样的加标回收率为92.8%~96.0%。用与粉煤灰成分相似的土壤国家标准物质GB W07405、GB W07406验证方法,测定值在标准值不确定度范围内,精密度RSD(n=12)为0.99%、0.73%。ICP-OES法测定煤及粉煤灰中伴生锂元素具有快速、简便和准确等特点,可实现锂元素的批量快速测定。  相似文献   
999.
In the present study, a coal‐integrated gasification combined cycle power plant is simulated. A high‐ash coal and low‐ash coal are considered to compare the performance of the plant. The combined cycle is in typical commercial size with 450 MW capacity. The feeds are Tabas and Illinois #6 coals which approximately contain more than 30% and 10% ash and have higher heating values of 22.7 MJ/kg and 26.8 MJ/kg, respectively. Energy and exergy analyses are done by aspen plus ® and ees , respectively. Energy analysis shows that the overall efficiencies of power plants using high‐ash and low‐ash coals are 33% and 28%, respectively. The result shows that in high‐ash case, 52 kg/s coal, 10 kg/s water, and 1050 kg/s air and in low‐ash case, 48 kg/s coal and 820 kg/s air are required for providing mentioned power, approximately. Exergy analysis shows that maximum exergy destruction is in heat recovery steam generator unit. Investigating the emissions shows that high percent of ash in the coal composition has slight effects on the IGCC pollution. Finally, from thermodynamic viewpoint, it is concluded that the high‐ash coal, like the conventional one, can be used as thermally efficient and environmentally compatible feed of IGCCs. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
1000.
叙述了国内煤矿地测管理的发展历程,分析了当前煤矿地测信息的特征和问题,基于煤矿地测管理信息系统的优势,提出了煤矿地测管理信息系统的构建和开发。  相似文献   
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