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Combustion Characteristics of Polyethylene and Coal Powder at High Temperature
To study the combustion characteristics of the polyethylene (PE) particle and coal powder at blast temperature of the blast furnace, the contents of CO and CO2 of off-gas during the combustion of PE particle and coal powder at the 1 200 ℃ and 1 250 ℃ were measured using carbon monoxide and carbon dioxide infrared analyzer, and then the corresponding combustion ratio was calculated. The results showed that when the temperature is high, the combustion speed of PE and coal powder is high and the corresponding combustion ratio is high. Whereas, the combustion speed and ratio of PE are much higher than those of coal powder....
2020-07-02 21:23:04浏览：1438
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Hydrogen Bonds in Coal——The Influence of Coal Rank and the Recognition of a New Hydrogen Bond in Coa
By means of in-situ diffuse reflectance FTIR, the IR spectra of 6 coals with different ranks were obtained from room temperature to 230 ℃. A new curve fitting method was used to recognize the different hydrogen bonds in the coals, and the influence of coal ranks on the distribution of hydrogen bonds(HBs) in the coals and their thermal stability were discussed. The results show that there is another new HB(around 2514 cm-1) between the -SH in mercaptans or thiophenols and the nitrogen in the pyridine-like compounds in the coals, and the evidence for that was provided. The controversial band of the HB between hydroxyl and the nitrogen of the pyridine-like compounds was determined in the range of 3028-2984 cm-1, and the result is consistent with but more specific than that of Painter et al.. It was found that the stability of different HBs in the coals is influenced by both coal rank and temperature. For some HBs, the higher the coal rank, the higher the stability of them. Within the temperature range of our research, the stability of the HB between the hydroxyl and the π bond increases to some extent for some coals at temperatures higher than 110 or 140 ℃....
2020-07-02 21:23:04浏览：1435
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Determination of the volatile fraction of coal tar
The coal tar was qualitative and quantitative analyzed by gas chromatography (GC) method. 74 components were identified exactly by gas chromatography-mass spectrometry (GC-MS). 31 components (37%) were quantitatively analyzed by gas chromatography-flame ionization detector (GC-FID). The linearity, accuracy, precision, limit of detection (LOD) and limit of quantitative (LOQ) determination were inspected. The scope of quantitative analysis by GC was discussed. The experimental results of thermogravimetric analysis (TGA) proved that GC quantitative analysis of the coal tar was reliable....
2020-07-02 21:23:04浏览：1445
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Prospecting for coal in China with remote sensing
With the rapid development of China's economy, coal resources are increasingly in great demand. As a result, the remaining coal reserves diminish gradually with large-scale exploitation of coal resources. Easily-found mines which used to be identiffed from outcrops or were buried under shallow overburden are decreasing, especially in the prosperous eastern regions of China,which experience coal shortages. Currently the main targets of coal prospecting are concealed and unidentified underground coal bodies, making it more and more difficult for coal prospecting. It is therefore important to explore coal prospecting by taking advantage of modern remote sensing and geographic information system technologies. Given a theoretical basis for coal prospecting by remote sensing, we demonstrate the methodologies and existing problems systematically by summarizing past practices of coal prospecting with remote sensing. We propose a new theory of coal prospecting with remote sensing. In uncovered areas, coal resources can be prospected for by direct interpretation. In coal beating strata of developed areas covered by thin Quaternary strata or vegetation, prospecting for coal can be carried out by indirect interpretation of geomorphology and vegetation. For deeply buried underground deposits, coal prospecting can rely on tectonic structures, interpretation and analysis of new tectonic clues and regularity of coal formation and preservation controlled by tectonic structures. By applying newly hyper-spectral, multi-polarization, multi-angle, multi-temporal and multi-resolution remote sensing data and carrying out integrated analysis of geographic attributes,ground attributes, geophysical exploration results, geochemical exploration results, geological drilling results and remote sensing data by GIS tools, coal geology resources and mineralogical regularities can be explored and coal resource information can be acquired with some confidence....
2020-07-02 21:23:04浏览：1397
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Synthesis of β-Sialon from Coal Gangue
It is worth to study the synthesis of β-Sialon from coal gangue, because coal gangue is a waste of coal production andis a high quality kaolin contained carbon which is a perfect raw material of contained reducer itself for synthesis of β-Sialon. The study showed that a high conversion rate of 95% from coal gangue to β-Sialon could be obtained by usingprocess of carbothermal reduction nitridation when strictly controlled the thermodynamic conditions of synthesis. Forcontrolling the synthesis conditions easy, the details of the effects of Pco, Po2 and T on the conversion rate of β-Sialon were discussed detailedly and the phase diagrams of oxygen pressure vs composition for Si3N4-AlN-Al2O3-SiO2system at 1350, 1500, and 1600℃ were constructed in the paper....
2020-07-02 21:23:04浏览：1440
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Clean Processing and Utilization of Coal Energy
The dominant status of coal on the energy production and consumption structure of China will not be changed in the middle period of this century. To realize highly efficient utilization of coal, low pollution and low cost are great and impendent tasks. These difficult problems can be almost resolved through establishing large-scale pithead power stations using two-stage highly efficient dry coal-cleaning system before coal burning, which is a highly efficient, clean and economical strategy considering the current energy and environmental status of China. All these will be discussed in detail in this paper....
2020-07-02 21:23:04浏览：1403
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Coal petrology and genesis of Jurassic coal in the Ordos Basin, China
Multiple sets of thick coal beds characterized by simple structure and shallow burial depth were developed in the Early and Middle Jurassic strata of the Ordos Basin,northwestern China.The huge reserves of this high quality coal have a high commercial value.We studied the coal's petrologic characteristics and its maceral distribution to determine the maceral's contribution to generation of oil and gas.The results show that the Jurassic coals in the Ordos Basin have special petrological features because of the Basin's unique depositional environment which was mainly a series of high-stand swamps in the upper fluvial system.These petrographic features are a result of the development of typical inland lakes where some sand bodies were formed by migrating rivers.After burial,the peat continued to undergo oxidizing conditions,this process generated extensive higher inertinite contents in the coals and the vitrinite components were altered to semi-vitrinite.The macroscopic petrographic types of these Jurassic coals are mainly semi-dull coal,dull coal,semilustrous and lustrous coal.The proportions of semi-dull coal and dull coal are higher in the basin margins,especially in the area near the northern margin.The numbers of semilustrous and lustrous coals increase southwards and towards the central basin.This situation indicates that different coal-forming swamp environments have major controlling effects on the coal components.Another observation is that in the Ordos' coal sequences,especially in the lower part,some sandstone beds are thick,up to 20 m with a coarse grain size.The higher fusinite content in the macerals accompanies a higher semi-vitrinite content with more complete and regular plant cell structure.The fusinite structure is clear and well preserved.After burial,the lithology of the roof and floor rocks can continue to affect the evolution of coal petrology.The sand bodies in the roof and floor exhibit good physical conditions so that pore water can maintain a long-term state of oxidation,circulation and connection to the coal.So coal components remain in an oxidation environment for a long time.Conversely,in the basin center,lacustrine facies developed and peat was rapidly covered by mudstone after burial and subsequent coal beds rapidly entered a reducing environment.As a result,abundant gelatification occurred and the vitrinite content increased.Exinite often accumulated in a specific position in the coal bed.Although the average exinite content is not high on the whole,it does significantly contribute to the total hydrocarbon generation.The exinite content has been underestimated,especially the amorphous bituminous fluid and its importance is emphasized here.The reason is that the fluid flows easily into fusinite which has strong rigidity,or flows into some fissures,where it is commonly neglected....
2020-07-02 21:23:04浏览：1403
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Damage statistical mechanics model of top coal in steep top caving coal
Damage statistical mechanics model of horizontal section height in the top caving was constructed in the paper. The influence factors including supporting pressure, dip angle and characteristic of coal on horizontal section height were analyzed as well. By terms of the practice project analysis, the horizontal section height increases with the increase of dip angle β and thickness of coal seam M. Dip angle of coal seam β has tremendous impact on horizontal section height, while thickness of coal seam M has slight impact. When thickness of coal seam is below 10m, horizontal section height increases sharply. While thickness exceeds 15 m, it is not major factor influencing on horizontal section height any long....
2020-07-02 21:23:04浏览：1427
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Influence of Lithological Characters of Coal Bearing Formation on Stability of Roof of Coal Seams
Lithology is one of the important factors influencing the stability of roof of coal seams. In order to investigate this, the phenomenon of underground pressure and distribution of pressure were studied by using the local observation and simulation test with similar materials. The observation results show that the distance of initial weighting and periodic weighting of the mudstone roof is shorter than that of sandstone roofs. The sandstone roof with a high strength has a longer distance of initial weighting and periodic weighting, the abutment stress on the working face is big and the height of caving and fracture zone is high. The peak point of abutment stress in the sandstone roof is near to the working face and the pressure bump is inclined to occur. The result is contrary to that in case of the mudstone roof with a low strength. While in the transition zone of nipped sandstone, roof rock-mass is broken and is poor in stability, therefore, it is difficult to hold the roof....
2020-07-02 21:23:04浏览：1422
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Effect of coal slurry on the corrosion of coal-mine equipment
The corrosion of coal mine equipment immersed in coal slurry is addressed.The corrosion of low carbon steel samples immersed in coal slurries of different concentrations (80,130,and 180g/L) prepared from coals of different rank (long-flame coal,meager lean coal,and anthracite) and different granularity (0.25-0.5 mm,0.074-0.25 mm,and less than 0.074 mm particle size) was studied by the electrochemical method of polarization curve measurement,controlled potential sweeping,and continuous scanning.The results show that the corrosion rate in an anthracite slurry,where the coal has high coalification,is far greater than corrosion in a long-flame or a meager lean coal slurry.Furthermore the corrosion current,polarization current,and corrosion rate of low carbon steel become larger,and the polarizability becomes smaller,as the coal particle size decreases.The same trend is seen as the concentration of the coal slurry increases....
2020-07-02 21:23:04浏览：1424
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Distribution of Heavy Hydrocarbon in Coal Seams and Its Use in Predicting Outburst of Coal
In order to verify whether any special gas component exists in outburst samples or not, coal samples from both outburst coal seams and non-outburst coal seams were collected. Some gases were extracted from the samples and analyzed qualitatively and quantitatively on chromatogram-mass spectrograph. The qualitative analysis show that there is no special gases in coal seams. And the quantitative analysis indicates that the heavy hydrocarbon content in coal samples from outburst coal seams is apparently higher than that from non-outburst district ones, which reflects the damage of geological tectonic movement to coal body in history. Therefore, the heavy hydrocarbon content of coal sample can be used as an index to predict coal outburst....
2020-07-02 21:23:04浏览：1421
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Crossing point temperature of coal
A further understanding of the self-heating of coal was obtained by investigating the crossing point temperature (CPT) of different ranks of coal. The tests were carried out using a self-designed experimental system for coal self-heating. 50 g (±0.01 g) of coal particles ranging from 0.18 mm to 0.38 mm in size were put into a pure copper reaction vessel attached to the center of a temperature programmed enclosure. The temperature program increased the temperature at a rate of 0.8 ℃/min. Dry air was permitted to flow into the coal reaction vessel at different rates. The surrounding temperature and the coal temperature were monitored by a temperature logger. The results indicate that CPT is affected by coal rank, moisture, sulfur,and the experimental conditions. Higher ranked coals show higher CPT values. A high moisture content causes a delay phenomenon during the self-heating of the coal. Drying at 40 ℃ decreases the effects of moisture. The reactivity of sulfur components in the coal is low under dry and low-temperature conditions.These components form a film that covers the coal surface and slightly inhibits the self-heating of the coal.The flow rate of dry air, and the heating rate of the surroundings, also affect the self-heating of the coal. The most appropriate experimental conditions for coal samples of a given weight and particle size were determined through contrastive analysis. Based on this analysis we propose that CPTs be determined under the same, or nearly the same conditions, for evaluation of the spontaneous combustion of coal....
2020-07-02 21:23:04浏览：1410
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制备烯烃的各类原料的现状与发展前景
长期以来，生产乙烯的原料主要为石油和天然气。目前油气价格飞涨、资源日益匮乏，非油气的多元化资源的开发利用受到各国广泛重视。文章综述了生产烯烃的各类原料的现状及发展前景。现阶段以油气资源为原料的蒸汽裂解工艺是生产乙烯的主要手段，乙醇制烯烃工艺在巴西获得重大突破，煤制烯烃工艺正在中国实现工业化，将获得较大发展。...
2020-06-12 16:10:24浏览：1415
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能源价格对国内煤制烯烃产业的影响
针对国内外煤炭、石油、天然气等主要能源产品近年来的价格走势及相关性,分析全球新的能源价格体系对中国能源价格的影响.研究表明:近年来北美页岩气的大规模开发和利用导致能源价格体系受到冲击,以美国为主的页岩油气主要开采国对全球能源供应依赖性减弱,北美天然气价格持续下跌,西德州WTI与布伦特Brent原油价差不断拉大；煤炭产能过剩已使美国更多煤炭贸易转向亚洲,并成为拉低中国煤价的重要推手；而国内外能源价格变化对国内煤制烯烃产业也带来复杂影响,只有通过产业升级才能形成中国煤化工产业核心竞争力....
2020-06-12 16:09:36浏览：1402
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低温甲醇洗技术在16万吨/年煤制油装置中的应用
介绍了伊泰16万吨/年煤制油示范项目中低温甲醇洗工艺的应用情况，阐述了该工艺在安装和运行中存在的问题以及改进措施。运行结果显示，改造效果较好，甲醇消耗控制在1.13kg/m3，系统中的水含量降低至0.5%以下，用变换气代替低压蒸汽每年节约蒸汽用量60680 t。分析了该工艺流程的特点。实践证明该工艺先进成熟，净化度高且净化气质量稳定，能够满足生产需要，在煤炭间接液化示范装置中的应用是成功的。...
2020-06-12 15:50:04浏览：1410
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