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961.
西北地区煤炭资源及开发潜力 总被引:1,自引:5,他引:1
西北地区蕴藏着十分丰富的煤炭资源,占我国煤炭资源预测总量的76.46%。含煤盆地主要有鄂尔多斯、准噶尔、吐哈、塔北等。其中,鄂尔多斯煤盆地是具有稳定克拉通基底,沉积了石炭一二叠纪华北型海陆交互相含煤地层和三叠一侏罗纪内陆河流一湖泊型陆相含煤地层的双纪巨型含煤盆地;准噶尔煤盆地、吐哈煤盆地、塔北煤盆地是具有稳定陆块基底的侏罗纪内陆湖泊含煤盆地;伊犁煤盆地、尤尔都斯煤盆地、焉誉煤盆地和库米什煤盆地是具有天山华力西期摺皱带基底的山间断陷(坳陷)型含煤盆地;走廊煤盆地群是具有祁连加里东褶皱带基底的山间断陷(坳陷)型含煤盆地.阿拉善地块、柴达木地块晚古生代和中生代亦具备成煤的古地理条件,目前已在柴达木地块北缘和阿拉善地块南缘发现了小型煤盆地群。地块主体为沙漠覆盖,勘探程度低,可作为西北地区煤炭资源的后备潜力区块。 据国家煤炭工业局1998年统计,西北地区煤炭资源保有储量为4035.35X10~8t,其中生产井和在建井保有储量为752.24X10~8t。尚未利用的精查储量为187.69X10~8 t,可供进一步勘探的详查储量为510. 51 X 108 t >普查和找煤储量为2550.91X108t,煤炭资源储量丰富。我国2002年煤炭消费达到13.69XlO~8t. 2003年17.36X10~8t, 2004年达19X10~8t,而西北地区煤产量在全国所占比例甚小,根据中国煤炭工业协会对2004年1月统计,全国煤矿合计原煤产量为11170.75X10~4t,其中西北地区为1585.17X10~4t(内蒙古按全区产量的2/3计算),只占14.19%,西北地区煤炭资源开发潜力巨大。 相似文献
962.
Establishment of new structural indices for the coals with various susceptibilities to self-ignition
Turchanina Oksana Achim Bechte Smirnov Michael 《中国地球化学学报》2006,25(B08):51-51
One of the main aims of the coal industry is to improve conditions and increase the safety of the work. The questions of environment also need to be considered. In the complex of science-technological problems the focus is placed on how to reveal spontaneous combustion of coals and siltages. The results of spontaneous combustion of coals and siltages are bereavement of the minerals, promise for failures and accidents, and pollution of the environment. The decision of problem of the prevention is very hard, because the spontaneous combustion of coals is an unforeseeable and poorly studied process. The methods of preventing spontaneous combustion of coals must be established. In the first place, these investigations must start with the study of the structure of these coals. The aim of the present work is to determine the differences in the structure of coals with various susceptibilities to spontaneous combustion .Main methods of studying coals include ultimate and proximate analyses, petrographic analysis, analysis of ashes, X-ray (apparatus "Kristalloflex Siemens" using filtered cuprum radiation), extraction (Dionex ASE 200), gas chromatography-mass spectroscopy (GC-MS) Finnigan MAT GCQ. Proximate, ultimate and petrographic analyses revealed the distinction in the structure of coals with various susceptibilities to self-ignition. 相似文献
963.
Mingzhe ZHAI Otlogetswe Totolo Motsoptse P. Modisi Robert B. Finkelman Mingzhe ZHAI 《中国地球化学学报》2006,25(B08):53-54
Coal is an important natural resource in Botswana. The best coals so far found occur in the Morupule coalfield, west of Palapye, where nearly 8000 million tons have been identified (Carney et al., 1994). In this study we investigate the environmental impact of the mining and consumption of the high-ash, medium-calorific value bituminous coal in the eastern part of Botswana, which may serve as a reference for other coal mines and coal-based power stations around the globe. More than two hundred surface soil samples and three profile soil samples were collected around Morupule Colliery, Morupule Power Station and Palapye. 相似文献
964.
Hongcang ZHOU 《中国地球化学学报》2006,25(B08):54-55
Direct coal combustion not only has a low utilizing efficiency, but also produces a large amount of pollutants such as particulate, CO2, SO2, NOx, polycyclic aromatic hydrocarbons (PAHs), PCDD/PCDFs, and so on. Coal gasification is a clean coal technology that presents good prospects for coal use, mainly for producing electricity with a high coal conversion efficiency and low environmental impact. However, there is a problem about the minimization of PAHs in coal gasification or direct coal combustion. PAHs are harmful to the environment and human health due to their high degree of mutagenicity and carcinogenicity when they enter human bodies through breathing, eating, and drinking. It is said that about 75%-90% cancers of human beings are mainly caused by PAHs. So the US EPA has prioritized 16 PAH compounds as hazardous air pollutants; these compounds are naphthalene (NAP), acenaphthylene (AcPy), acenaphthene (AcP), fluorene (Flu), phenanthrene (PhA), anthracene (ANT), fluoranthene (FluA), pyrene (Pyr), benzo (a) anthracene (BaA), chrysene (Chr), benzo (b) fluoranthene (BbF), benzo (k) fluoranthene (BkF), benzo (a) pyrene (BaP), indeno(1,2,3,-cd) pyrene [In(1,2,3-cd) P], dibenzo (a,h) anthracene (DbA), and benzo (ghi) perylene (BghiP). The residual char is one of the main products during coal gasification, and then it is brought into the combustion chamber to combust. To investigate the distribution of PAHs in fly ash, the combustion of coal and residual char was tested in a pressurized spouted fluidized bed. After Soxhlet extraction and K-D concentration, the contents of 16 PAHs recommended by US EPA in coal, residual char, and fly ash, were analyzed by a HPLC coupled with fluorescence and diode-array detection. 相似文献
965.
基于多重小波的海洋重力异常畸变消除方法 总被引:1,自引:1,他引:1
分析了信号在多重小波算法下的表现形式,采用软阈值方法对经过多重小波变换后的重力异常信号的高频部分进行阈值处理.根据离散的重力异常状态方程,采用HGM多重小波进行了海洋重力异常数据仿真处理.理论分析和仿真处理表明:采用软阈值处理方法和联合软阈值处理方法以及特征值法阈值选择规则,都能在一定程度上消除海洋重力异常畸变.但在相同背景条件下,联合软阈值处理方法的性能优于软阈值处理方法. 相似文献
966.
构造应力对煤化作用的影响*——应力降解机制与应力缩聚机制 总被引:4,自引:0,他引:4
压力因素在煤化作用中的意义是一个长期争议的问题,其主要原因在于混淆了地层压力和构造应力两种不同性质的“压力”作用,前者有利于物理煤化作用但抑制化学煤化作用,后者对物理煤化作用和化学煤化作用均具有促进作用。与有机大分子演化途径相适应,构造应力影响化学煤化作用存在两种基本机制——应力降解和应力缩聚。应力降解是指构造应力以机械力或动能形式作用于煤有机大分子,使煤芳环结构上的侧链、官能团等分解能较低的化学键断裂,降解为分子量较小的自由基团,以流体有机质形式(烃类)逸出的过程。应力缩聚是指在各向异性的构造应力作用下,煤芳环叠片通过旋转、位移、趋于平行排列使秩理化程度提高,基本结构单元定向生长和优先拼叠、芳香稠环体系增大的过程。采用X衍射(XRD)、傅立叶红外(FTIR)和岩石热解(Rock-eval)等技术,进行构造煤系列和非构造煤系列的对比分析,结果表明,构造变形煤具有脂族吸收峰弱而芳核吸收峰强、热解生烃潜力相对较低、基本结构单元增大等显著特征。应力降解和应力缩聚机制的提出,并未否认有机质演化的温度主导作用,只是强调构造应力在煤化作用中的“催化”意义。 相似文献
967.
968.
LIU Yanxue LIU Yongqing ZHANG Hong 《《地质学报》英文版》2006,80(5):733-742
LA-ICPMS Zircon U-Pb dating is applied to volcanic rocks overlying and underlying the Salamander-bearing bed in the Daohugou beds of Ningcheng in Inner Mongola and Reshuichang of Lingyuan and Mazhangzi of Jianping in western Liaoning. The results indicate that the youngest age of the rocks in Daohugou of Ningcheng is 158 Ma, and the oldest one is 164 Ma. Synthesized researches indicate that the salamander-bearing beds in Daohugou of Ningcheng, Reshuichang of Lingyuan and Mazhangzi of Jianping were developed in the same period. The Daohugou beds were formed in the geological age of 164-158 Ma of the middle-late Jurassic. Whilst, the Daohugou beds and its corrdative strata should correspond to the Tiaojishan Formation (or Lanqi Formation) of the middle Jurassic in northern Hebei Province and western Liaoning Province, based on the disconformity between the Daohugou beds and its overlaying beds of the Tuchengzi Formation of Late Jurassic and the Jehol Beds of early Cretaceous, and the disconformity between the Daohugou Beds and its underlying Jiulongshan Formation, which is composed of conglomerate, sandstone, shale with coal and thin coal beds. 相似文献
969.
1 IntroductionThe compositional characteristics of natural gasesand their carbon isotopic composition are controlledmainly by the type of organic matter and the degree ofits thermal evolution in the source rocks (Song Yan,1995; Xu Yongchang et al., 1994; … 相似文献
970.
1 Introduction In recent years rapid economic developmentbadly needs energy resources. Exploration andexploitation of more kinds of energy resources shouldbe intensified to meet this need. According to presentliterature, oil/gas fields, coal fields as we… 相似文献