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1.
为提高土壤及水系沉积物中全硫含量测定结果准确度,提出了库仑滴定法进行全硫量测定的方法优化,探究了称样量、炉温、载气流量和催化剂种类等不同因素影响对土壤及用水系沉积物中硫含量的测定准确度的影响。测试结果表明：库仑滴定法测定土壤及水系沉积物中硫含量的最佳工作条件为炉温1 200℃,称样量0.100 0g,载气流量1.0 L/min;纯铁催化剂对于极高或极低硫值样品的测定结果稳定度更高,WO3催化剂具有更高的性价比;库仑滴定法相较于燃烧-碘量法和高频红外法对低硫含量样品测定更准确。相较于燃烧-碘量法和高频红外法,库仑滴定法对低硫含量样品测定更准确。 相似文献
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江西省煤炭工业局煤田试验室 《煤田地质与勘探》1974,2(1):55-58
煤中全硫含量的测定方法,目前多采用经典的艾氏卡重量法。有的单位曾提出燃烧酸碱中和法,其分析手续较重量法简单,但较燃烧碘量法复杂,测定速度较慢。我们对煤中全硫,用测定岩石中三氧化硫的燃烧碘量法进行了测定试验,结果较好。 相似文献
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滇东北镇雄煤田晚二叠世煤中硫的可选性 总被引：1，自引：0，他引：1
通过对云南省东北部昭通市镇雄干沟乡荣兴煤矿C5煤层原煤筛分浮沉实验的研究,分析了该煤层中全硫及形态硫在不同粒度级和密度级中的分布规律。结果显示,全硫和黄铁矿硫在各粒度级煤中分布较均匀,其含量在各密度级煤中的分布随密度级的增大而增大。该煤层的破碎解离性质较差,但其粒度小于3.0 mm时,可分离出含2.35%全硫的浮煤(浮煤产率达88%)。总体来看,高密度级中,黄铁矿硫>95%;低密度级中,黄铁矿硫<65%,有机硫占30%左右,但其全硫较低。因此,可通过物理方法使浮煤中的硫分降低。 相似文献
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兖州矿区山西组 3煤层中微量元素的特征分析 总被引：7，自引：2，他引：7
通过对兖州矿区山西组3煤层21个样品中全硫、硫化物硫、有机硫和具有环境意义的微量元素Cu、Pb、Zn、As、U、Th含量的测试，分析了微量元素在研究区煤层垂直方向上的变化特征及主要形成原因，并发现煤层中所选的微量元素、硫化物琉及全硫在煤层顶、底或煤层夹矸样品中含量相对较高。微量元素与硫化物硫、全硫的相关系数表明，所研究的微量元素与硫化物硫和全硫有明显的正相关关系，而且研究区3煤层中全硫的含量取决于硫化物硫的含量。同时还研究了原煤中微量元素的含量与灰产率的关系，并将研究区微量元素同世界和中国同类煤中的微量元素的含量进行了比较。 相似文献
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内蒙古乌达矿区煤中硫的同位素组成及演化特征 总被引：13，自引：0，他引：13
通过对内蒙古乌达矿区高硫煤９煤层和低硫煤１３煤层剖而上有机硫和黄铁矿硫同位素的测定,结合煤岩学综合分析,着重论述了煤中硫同位素的分布特点及成因,分析了有机硫同位素和黄铁矿硫同位素之间及其和全硫的关系,提出高硫煤硫同位素形成过程中在剖面上具有层次性和时间上具有相向性,层次性表现为随泥炭沼泽深度的增加,体系对ＳＯ４＾２－和Ｈ２Ｓ的开放程度及黄铁矿的形成对＾３２ＳＯ４＾２－的过滤性;相向性有仅表现为泥岩 相似文献
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应用扫描电镜对煤中不同显微组分中有机硫进行了测定。应用XPS方法测定了8号煤中有机硫的存在形态，评述了煤中硫的变化规律。论述了古交矿区主要可采煤层中黄铁矿硫的形态特征和分布规律。 相似文献
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沁水盆地晚古生代煤中硫的地球化学特征及其对有害微量元素富集的影响 总被引：1，自引：0，他引：1
煤中硫是多种有害微量元素的重要载体。基于形态硫分析、电感耦合等离子质谱及X射线衍射等方法分析沁水盆地晚古生代煤中硫和有害微量元素的分布规律,探讨了煤中硫对有害微量元素富集的影响,运用带能谱的扫描电镜和光学显微镜划分煤中硫化物的微观赋存特征。结果表明,沁水盆地煤中硫整体上以有机硫为主,平均占全硫的78%,只有在太原组个别高硫煤中以黄铁矿硫为占优势。显微镜和扫描电镜下可识别出煤中黄铁矿的微观赋存状态包括莓球状、薄膜状、晶粒状、结核状、团窝状黄铁矿和细粒黄铁矿集合体,白铁矿的微观赋存特征包括聚片状、板状和矛头状白铁矿,部分白铁矿与黄铁矿共生。沁水盆地煤中有害微量元素含量整体较低,黄铁矿是有害微量元素As、Se和Hg的重要载体,而有机硫决定了煤中U的富集。研究认为,成煤时期海水对泥炭沼泽的影响导致太原组煤中全硫和黄铁矿硫较高,太原组煤中硫的来源具有多样性,煤中黄铁矿具有多阶段演化的特点。 相似文献
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中高含硫量煤中硫的形态分析 总被引：5，自引：0，他引：5
利用超声提取、高速离心分离和加入助分散剂等手段，实现了中，高含硫量煤中单质硫，硫酸盐硫，硫化物硫，有机硫等主要形态硫的分步提取和顺序测定。所建分析方法测定了国家一级标样，统样样品和部分有分析结果的样品，其主要形态硫的加和与标准样品参考值，统检样品定值，原样品的总硫分析结果相符，RSD（n=3)为0．80％－4．23％，方法可用于煤中各主要形态硫的测定。 相似文献
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Chengpeng Xin Kai Wang Feng Du Xiang Zhang Gongda Wang Yilei Liu 《Arabian Journal of Geosciences》2018,11(23):747
It is of great significance for the analysis and prediction of coal-gas outburst disasters to understand the mechanical properties and permeability evolution of coal and rock under conditions of stope stress evolution. In this study, mechanical tests were conducted on gas-bearing coal under four stress paths, including conventional triaxial compression (CTC), phased variable speed triaxial compression (PVSTC), unloading confining pressure (UCP), and phased variable speed unloading confining pressure (PVSUCP), simultaneously measuring the permeability in mechanical tests. The mechanical properties and permeability evolutions in gas-bearing coal under four different stress paths were compared. The obtained results show that the deviatoric stress-strain curves of gas-bearing coal under four stress paths could be divided into five stages: compaction, linear elasticity, plastic deformation, stress drop, and residual stress stage. The permeability-strain curves under four stress paths could also be divided into five stages: fast drop, slow decrease, slow increase, sharp increase, and slowed growth. Compared to the CTC conditions, the peak strain and strength of coal under PVSTC conditions increased. Furthermore, the stress drop and energy release under PVSTC were more intense at the moment of instability failure. Compared to both loading paths, the coal was damaged more rapidly under unloading paths and the damage was stronger. Additionally, among both unloading paths, the time required for the failure of coal under PVSUCP was shorter than that under UCP, while the damage under PVSUCP was stronger. The strength characteristics of the gas-bearing coal under PVSTC and PVSUCP still met the Mohr–Coulomb criterion. This preliminary study has guiding significance for the understanding of the co-occurrence mechanisms of coal-gas outburst disasters. 相似文献
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The isotopic compositions of S (δ34S) and C (δ13C) were determined for the coal utilized by a power plant and for the fly ash produced as a by-product of the coal combustion in a 220-MW utility boiler. The coal samples analyzed represent different lithologies within a single mine, the coal supplied to the power plant, the pulverized feed coal, and the coal rejected by the pulverizer. The ash was collected at various stages of the ash-collection system in the plant. There is a notable enrichment in 34S from the base to the top of the coal seam in the mine, with much of the variation due to an upwards enrichment in the δ34S values of the pyrite. Variations in δ34S and in the amount of pyritic S in the coal delivered to the plant show that there was a change of source of coal supplied to the plant, between week one and week two of monitoring, supporting a previous study based on metal and sulfide geochemistry for the same plant. The fly ash has a more enriched δ34S than the pulverized coal and, in general, the δ34S is more enriched in fly ashes collected at cooler points in the ash-collection system. This pattern of δ34S suggests an increased isotopic fractionation due to temperature, with the fly ash becoming progressively depleted in 34S and the flue gas S-containing components becoming progressively enriched in 34S with increasing temperatures. Substantially less variation is seen in the C isotopes compared to S isotopes. There is little vertical variation in δ13C in the coal bed, with δ13C becoming slightly heavier towards the top of the coal seam. An 83–93% loss of solid phase C occurs during coal combustion in the transition from coal to ash owing to loss of CO2. Despite the significant difference in total C content only a small enrichment of 0.44–0.67‰ in 13C in the ash relative to the coal is observed, demonstrating that redistribution of C isotopes in the boiler and convective passes prior to the arrival of the fly ash in the ash-collections system is minor. 相似文献
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《International Geology Review》2012,54(6):482-484
P. I. Stepanov suggested that during the Cretaceous there probably took place a considerable accumulation of coal, although that time was always considered to have been a period of attenuation of coal accumulation. The analysis of facies of the Cretaceous deposits in the far east maritime region of the U. S. S. R. as well as of those of Alaska led the author to conclude that coal accumulation during the Cretaceous was tremendous. This conjecture has now been confirmed: the new estimate of coal reserves of the U. S. S. R. has shown the Cretaceous Lena coalfield to be the largest in the world. Tremendous reserves of coal are also concentrated in the Bureya, Maritime, Anadyr and Sakhalin Cretaceous coal bearing basins of the U. S. S. R. in the Ryōseki basin of Japan and in the Cretaceous coal deposits of North America, particularly in Alaska where a major coalfield very likely exists. Thus it may now be considered that during the Cretaceous there accumulated reserves of coal comparable in immensity to those accumulated during the Tertiary and undoubtedly much larger than those of the Permian, Carboniferous and Jurassic. It may be asserted that rate of coal accumulation kept ever increasing in the course of geological time, and the Cretaceous may be regarded as a period of very intensive coal accumulation. Following up Stepanov's idea we can point out the knots of Cretaceous coal accumulation: Lena, Alaska, Anadyr, Sakhalin — Maritime. The new data on the Cretaceous coal accumulation should be taken into account in any reconstruction of the history of geological development of the earth and of the evolution of the organic world. --Author's English Summary. 相似文献
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塔北—南天山地区震旦—奥陶纪盆 山构造演化及其与油气关系 总被引：2，自引：0，他引：2
震旦—奥陶纪时期塔北与南天山地区在“新疆古克拉通”的基础上经历了一个伸展、裂离和挤压、聚合的完整旋回。该区由南向北大致可分为３个近于平行的与伸展作用有关的构造区带：（１）南库鲁克塔格裂陷槽—满加尔克拉通边缘坳陷—塔里木克拉通内坳陷；（２）北库鲁克塔格—铁门关—老虎台隆起带；（３）南天山洋盆。该时期的构造演化可大致分为３个阶段：（１）震旦纪伸展 裂陷阶段；（２）寒武纪—早奥陶世伸展 裂离阶段；（３）中—晚奥陶世挤压 聚合阶段。具有伸展盆地性质的满加尔克拉通边缘坳陷是该区的主力生油坳陷，其热演化程度高，位于其北侧的继承性古隆起及斜坡是主要的油气运移指向和聚集场所。 相似文献
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SHEN Yulin QIN Yong CUI Min XIE Guoliang GUO Yinghai QU Zhenghui YANG Tianyang YANG Liu 《《地质学报》英文版》2021,95(1):91-104
Coal-bearing source rocks of the Pinghu Formation in the Xihu Depression comprise an important material basis of oil and gas resources in the East China Sea Basin.Based on drilling core observation results combined with the analysis and test results of macerals,trace/rare earth elements,and rock pyrolysis,the geochemical characteristics and sedimentary control of coal-bearing source rocks formation are discussed in a high-frequency sequence framework.The results indicate that the macerals composition of the coal-bearing source rocks of the Eocene Pinghu Formation in the Xihu Depression is dominated by vitrinite,with low-medium abundance of exinite and almost no inertinite.The coals and carbonaceous mudstones display higher amounts of total organic carbon(TOC)(14.90%-65.10%),S1+S2(39.24-136.52 mg/g),and IH(191-310 HC/g TOC)respectively,as compared to the mudstones.Organic matter is plotted in typeⅢkerogens and partially in typeⅡ;it is mainly in the low maturity stage.The trace elements results imply that the samples were deposited in a weakly reducing to weakly oxidizing environment and were occasionally affected by seawater.The coal-bearing source rocks were deposited in a relatively oxygen-containing environment.The coal-bearing source rocks development is jointly controlled by the coal accumulation environment,the water conditions affected by ocean currents in offshore basins in China,oxidation-reduction cycles of aqueous media and paleoclimate evolution in a high-frequency sequence framework. 相似文献
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With the development of deep mining in recent years, coal and gas compound dynamic disasters become increasingly serious. In this study, uniaxial and triaxial compression tests were conducted on gas-bearing coals, coal–sandstone combined bodies and coal–mudstone combined bodies and the permeabilities in the triaxial tests were measured simultaneously. The mechanical behavior and seepage characteristics of coals and coal–rock combination bodies under triaxial conditions were compared in details. The results show that the peak strength among three samples is: coal–sandstone combined body > coal–mudstone combined body > coal. If other conditions were held constant, the strength and the elastic modulus of all specimens show that tendency increases with the increment of the confining pressure or with the decrease in the gas pressure. The strength characteristics of all three specimens met the Mohr–Coulomb criterion, and the residual strength has an increasing trend with the increase in confining pressure. The permeability evolutions of gas-bearing coals and coal–rock combination bodies which are determined by the crack propagation in the coals and rocks are not exactly the same. This preliminary study is intended to deepen our understandings of the mechanisms of coal–gas compound dynamic disasters and provide theoretical bases for their predictions. 相似文献
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Modes of Occurrence and Cleaning Potential of Trace Elements in Coals from the Northern Ordos Basin and Shanxi Province, China 总被引：1，自引：1，他引：0
WANG Wenfeng QIN Yong JIANG Bo FU XuehaiCollege of Mineral Resources China University of Mining Technology Xuzhou Jiangsu 《《地质学报》英文版》2004,78(4):960-969
Based on the analyses of 43 elements in 16 samples of the raw coal and feed coal collected from the northern Ordos basin and Shanxi Province, the modes of occurrence of these elements were studied using the method of cluster analysis and factor analysis, and the cleaning potential of the hazardous elements relatively enriched in the coals was discussed by analyzing six samples of the cleaned coal from the coal-washing plants and coal cleaning simulation experiments. The results shows that the elements Br and Ba show a strong affinity to the organic matter, Cs, Cd, Pb, Zn and Hg partly to the organic matter, and the other trace elements are mainly associated with the mineral matter. Cs, Mo, P, Pb, Zn and S have positive correlations with the two principal factors, reflecting the complexity of their modes of occurrence. Some elements that were thought to show a faint relationship (Be with S and Sb with carbonates) in other rocks are found to have a strong interrelation in the coals. Clay minerals (mainly k 相似文献
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内蒙古是我国非常重要的后备煤炭资源基地,煤层大多聚集在白垩纪断陷盆地中,其中,五间房含煤盆地煤炭资源丰富。通过对该盆地东南部3个钻孔57件煤样的煤岩学和煤化学分析,探讨了煤层的煤质特征、煤相类型及其演化规律。研究结果表明:本区煤层以低—中高灰、高挥发分产率和低—特低硫为特征;具有较高的镜/惰比和结构保存指数;煤相类型主要为潮湿森林沼泽相,自下而上,成煤泥炭沼泽覆水程度总体有所加深,上部泥炭沼泽具有水体逐渐加深的水进型特征,下部泥炭沼泽具有水体逐渐变浅的水退型特征。 相似文献
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煤成油地球化学研究现状与展望 总被引：11，自引：0，他引：11
重点评述与煤成油理论及勘探实践有密切关系、并在近几年取得重要进展的煤成烃演化模式、煤的生油能力及排油研究3方面的问题。指出：石油地质化学家已更深刻地认识到了煤成烃模式、阶段因地而异的复杂性;建立判别煤系源岩生油能力的标准是煤成油研究中最为重要的进展之一,其中以依据总生烃潜量（S1+S2）、氯仿沥青“A”和总烃含量与有机碳的相关关系建立的判别方案比较实用和有效;比较系统地评述了（与工业性煤成油气聚集有重要关系的）煤成烃排出问题的4种主要研究方法。进展、存在的问题和分歧。在此基础上,展望了对指导煤成油勘探有重要意义的煤系源岩的分布预测、倾油性的进一步判识及排出问题定量研究的发展趋势。 相似文献