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91.
Oil shale is an organic-rich, fine-grained sedimentary rock, containing kerogen, from which liquid hydrocarbons (called shale oil) can be produced. The oil shale deposits in the Tigray region are found in the northern parts of Ethiopia, Eastern Africa. They are of Upper Paleozoic in age, existing as remnants of the Cretaceous erosion period, underlain by tillites and overlain by sandstones. They were formed during the glacial retreat followed by marine deposition of shales in a basin created by the enormous load of the glaciers. The Ethiopian-Tigray oil shale deposits cover an area extending over approximately 30 km2, with an average mineable bed-thickness of 55 m, showing on the upper part inter-beds and laminations of shaley limestones. The oil shale resources in this region are estimated to be approximately 4 billion tonnes. The exploitation of the Ethiopian-Tigray oil shale deposits is an excellent alternative to fulfill the fuel and other petroleum products’ demand of Ethiopia. This study sheds light on the oil shale resources in the Ethiopian region of Tigray, as they are fairly investigated, regarding their geological characterization, and future strategies for their exploration and exploitation potential. In addition, the oil shale deposits in Jordan are also moderately investigated, as Jordan is considered a promising country for shale oil, taking into account that Jordan has no other hydrocarbon resources (such as crude oil and natural gas), unlike many other countries in the MENA (Middle East and North Africa) region, as MENA sets on “seas” of oil and natural gas. Furthermore, oil shale in the USA is also briefly investigated, as the USA is being the world’s largest country of oil shale resources and reserves. Also, some other issues related to the oil shale industry are investigated, such as economics, extraction technologies of shale oil, and the environmental impacts.  相似文献   
92.
本文提出了新型双层陶粒滤料池的研究成果.文中介绍了新型双层滤池的构造、设计参数和基本工作性能.  相似文献   
93.
采用快速冻融试验方法研究轻集料不同预湿程度对页岩陶粒混凝土抗冻性的影响。结果表明,预湿程度对标养28d页岩陶粒混凝土的抗冻性有影响,随着预湿程度的增加,抗冻性有所降低,但仍能满足300次冻融循环要求;而随着养护龄期的延长,预湿程度对页岩陶粒混凝土的抗冻性几乎没有影响。同时对抗冻机理做了初步的探讨。  相似文献   
94.
The insoluble organic residues from the hydrogenation of Tasmanites sp. oil shale have been characterized by Curie point pyrolysis combined with gas chromatography and computerized gas chromatography-mass spectrometry. The resulting pyrograms show that very little, if any, hydrogenation of the residues occurs. Rather, the initial step in the sequence is pyrolysis of the residue followed by hydrogenation of the liquid products. Major compounds identified from the pyrograms of the residues include alkene/alkane doublets, mixtures of diterpenoids and mono- di- and triaromatic compounds. Changes in the distribution of these compounds with changes in reaction conditions are discussed.  相似文献   
95.
辽河盆地大民屯凹陷油气性质及成因机制研究   总被引:12,自引:2,他引:10       下载免费PDF全文
大民屯凹陷油品性质复杂,既有含蜡量小于20%的正常油,又富含蜡量>20%的特高蜡油。经过原油物性、甾萜等分析,认为高蜡油油源岩沉积环境为较正常油贫粘土、盐度相对较高、相对闭塞的弱还原环境,其母质应由陆源高等植物和低等水生生物共同构成,且经微生物改造较强烈。正常油油源以高等植物为主体,处于相对氧化且富粘土的沉积环境。通过精细油源对比认为:大民屯凹陷高蜡油主要来源于沙四下部的"油页岩",而正常油母质主要为沙四上部和沙三四的厚层泥岩。综合分析认为高蜡油成因主要受控于沉积母质和沉积环境的双重控制,且因整个大民屯凹陷较低的热演化程度而使高蜡油得以保存。   相似文献   
96.
平动椭圆振动筛具有优良的性能和钻井液处理能力,已广泛应用于国内外油田泥浆的净化处理系统。文章介绍了用Pro/E软件对振动筛进行参数化设计、开发专用振动筛设计程序的方法。为提高振动筛的设计效率、推出新产品提供了强有力的支持。  相似文献   
97.
Crude shale oils from an aboveground and two in-situ retorting processes were characterized for 26 trace element constituents. The shale oils were pyrolysed from Green River Formation oil shale by pilot plant or semiworks-sized facilities. Trace elements were resolved into those predominantly associated with suspended shale fines or emulsified water, and those more intimately associated with the shale oil matrix. The abundance of the metals As, Co, Fe, Hg, Mo, Ni, Sb, Se, V and Zn were quantified in whole and fractionated shale oil samples; the possible chemical nature of several metals is discussed. Based on the shale oils examined, the following observations were noted: the shale oils contained moderately high levels of Fe (33–63 ppm) and As (9.3–29 ppm), and lower quantities of Co, Mo, Ni, Se and Zn (≈1–10 ppm); most trace metals were associated with asphaltene or resin components; relative to reported mean values for petroleum, the As, Co, Fe, Mo and Se were more prevalent in Green River shale oil; in-situ retorting processes appeared to introduce Mo into the product shale oil.  相似文献   
98.
Levent Ballice 《Fuel》2003,82(11):1317-1321
The volumetric swelling procedure was applied to Göynük and Beypazar? oil shales from Turkey by using 10 solvents and the cross-linking in the macromolecular network of oil shales were investigated using this technique. Results from solvent swelling measurements show that the volumetric solvent swelling of oil shales samples roughly follows the regular solution theory. The theory of solvent swelling of cross-linked polymers developed Flory-Rehner and extension of this theory by Kovac-Peppas was used to calculate number average molecular weight per cross-link of kerogen structure in oil shale samples. Results indicate no remarkable difference between values for Göynük oil shale (Kerogen Type I) and Beypazar? oil shale (Kerogen Type II).  相似文献   
99.
目前钻井过程中的一大技术难题是泥页碉与钻井液接触后,钻井液中滤液和微细颗粒可能进入泥页岩,引起泥页岩力学性质发生变化,强度下降,从而引发一系列井下复杂情况和事故,妨碍油气勘探开发的过程。在研究该问题时,需要了解页岩的水化特性,了解泥页岩水化过程中强度变化等。这些都需要适合的试验方法来测试和分析。针对泥页岩水化后强度降低的特点,研制出泥页岩水化时效评价仪器。该仪器结构紧,操作方便,能自动采集处理数据并打印出结果,具有较高的测量精度。测试数据和曲线对于分析不同泥页岩的水化特征和优选抑制性钻井液处理剂及防塌钻井液配方具有重要作用。  相似文献   
100.
借助煤的低温干馏方法及采用自制加热装置和温度控制调节仪,主要针对油页岩中含油率的测定方法以及影响因素进行了研究。实验中采用对油页岩进行低温干馏后测定产物中的水分,从而间接测定油页岩的含油率。同时,对测定过程中的影响因素进行了考察,得到最佳升温速率为15℃/min、干馏终温为500℃、持温时间为20 min、颗粒度<3 mm。  相似文献   
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