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1.
矿物质对桦甸油页岩热解产物影响特性   总被引:4,自引:0,他引:4  
对桦甸油页岩进行逐级酸洗并对原样及各级酸洗样品的热解产物进行了碳平衡计算以及气相色谱和傅里叶红外光谱实验,得到了矿物质对油页岩热解不凝性气体、半焦以及页岩油的影响特性。结果表明,碳酸盐可以促进有机碳和氢向页岩油中转化,而硅酸盐对有机碳和氢向页岩油中转化具有抑制作用,碳酸盐和硅酸盐均可以使得页岩油中氢碳原子比降低。碳酸盐促进了油页岩热解产油并抑制了干酪根向不凝气分解转化,而硅酸盐抑制了油页岩热解产油但对干酪根向不凝气的分解转化具有促进作用。碳酸盐和硅酸盐均可以促进热解不凝气中CO_2和H_2的生成,而对CO的生成具有抑制作用,碳酸盐可以抑制热解不凝气中碳氢化合物的生成,而硅酸盐对其生成具有促进作用。碳酸盐和硅酸盐均可以使得页岩油中脂肪链长度变短及异构化程度变大,并能够提高干酪根热解产物的芳构化程度。  相似文献   

2.
桦甸油页岩热解过程中热沥青的组成变化规律   总被引:1,自引:0,他引:1  
将桦甸油页岩分别在300、350、400、450、500和550℃热解得到半焦,对半焦进行逐级抽提和酸洗,得到自由沥青、碳酸盐束缚沥青和硅酸盐束缚沥青,采用柱层析、FT-IR和GC-MS表征不同沥青的化学组成和结构特征,探讨沥青的化学组成变化及与矿物质的相互作用。结果表明,沥青总产率先增大后减小并在400℃取得最大值4.63%,400-450℃大量沥青分解生成页岩油,使沥青产率降至0.98%。350-450℃自由沥青主要发生羧酸脱羧、酯基分解和长链烷烃裂解反应,使羧酸和酯类化合物含量降低、烷烃碳链长度缩短。干酪根分解生成的羧酸与碳酸盐反应生成羧酸盐,使400℃碳酸盐束缚沥青中羧酸含量达78.82%;含氧化合物可与黏土矿物结合,且烷烃可进入蒙脱石层间,使400℃硅酸盐束缚沥青中含氧化合物和烷烃各占80.79%和19.21%。  相似文献   

3.
煤中矿物质及其燃烧后的变化分析   总被引:10,自引:9,他引:10  
以淮北煤田6煤层煤为样品,采用中子活化法、化学方法、X射线衍射及扫描电镜等方法对煤及其灰样品中的矿物质、微量元素进行了分析,在此基础上,研究了样品中主要矿物的种类及其形成时的影响因素,分析了它们在燃烧前后的主要变化。通过分析可知,样品中主要含有高岭石、石英、方解石和黄铁矿以及多种微量元素;在燃烧过程中,微量元素的含量以及矿物的种类发生了变化,并形成高温稳定的矿物种类。  相似文献   

4.
煤中矿物质对NO—半焦还原反应的影响   总被引:16,自引:8,他引:8  
选用四种不同煤阶的煤,经过HCl/HF脱灰处理制得四种脱灰煤,950度下热解制得原煤半焦和脱灰煤半焦,在石英固定床的以应器上于常压条件下400度-900度的温度范围内考察比较了原煤半焦和脱灰煤半焦半焦还原NO的反应性,研究了煤中矿物质 对NO-半焦还原反 的机理和反就动力学的影响,结果发现,煤中的矿物质一般对NO-半焦反应具有一定的催化作用,催化作用的大小与矿物质的含量和组成有关,钠,铁和钙等是矿物质中活性分,对NO-半焦反应具有催化作用,半焦还原NO的反应存在明显的双温区现象,低温反应机理与高温反应机理不同,活化能有明显差异。  相似文献   

5.
本文在考虑油页岩燃烧过程中热解挥发份燃烧产生的火焰能量反馈以及矿物质分解所得碱性氧化物的自固硫效应这两方面影响,并耦合了辐射、对流和传导三种形式的传热及氧气与二氧化硫传质和化学反应动力学的基础上,建立了颗粒油页岩流化床燃烧释放二氧化硫的非稳态渐进扩散反应的通用模型。对所得多变量的偏微分方程组开发了一个有界Wegstein数值求解方法,具有收敛快,计算精度高等优点。数值计算表明,对茂名油页岩,热解阶段的火焰温度比床温高出120℃左右,促进了热解析硫的过程;油页岩半焦中氧化钙的自固硫转化率达40~60%。  相似文献   

6.
利用固定床反应器研究了哈密煤温和液化固体产物(MLS)在热解过程中含硫气体的释放规律以及不同形态硫的变迁规律,并分析了矿物质对硫变迁规律的影响。结果表明,在实验考察的条件范围内,MLS热解过程中大部分的硫残留在半焦中,仅有不到10%的硫迁移到焦油中或转化为含硫气体逸出。热解生成的含硫气体以H2S为主,当热解温度为400℃时H2S的逸出速率达到最大。通过改进方法测定了M LS及其热解半焦中各种形态硫的含量,发现M LS热解过程中以硫化物硫和有机硫的分解和转化为主。随着热解温度的升高,MLS中有机硫逐渐分解并以含硫气体的形式逸出;当热解温度低于600℃时,M LS中硫化物硫逐渐转化为含硫气体、有机硫和少量的黄铁矿硫;当热解温度高于600℃时,M LS中碱性矿物质吸收气相中的H2S转化为硫化物硫,硫化物硫缓慢增加。醋酸酸洗可以保留M LS中大部分的硫化物硫,且酸洗后M LS热解生成的H2S逸出速率增大,峰温向低温方向移动;当热解温度高于600℃时,有机硫和硫化物硫的脱硫反应速率降低,并且M LS中的碱性矿物质与H2S反应生成金属硫化物,导致H2S逸出速率明显降低。  相似文献   

7.
用过氧化氢湿法灰化与等离子体氧低温灰化(LTA)法测定了茂名和抚顺油页岩矿物质的含量,结果是残渣收率比高温灰化的灰分值高约10%。用IR、XRD 与SEM-XPS 等方法对这两种油页岩矿物质的组成进行了分析,确认其主要组分为夹杂有石英的高岭石与水云母等粘土矿物,同时还有少量碳酸盐岩、硫铁矿、钾长石与铵长石等。据此,讨论了矿物质对油页岩分析以及加工利用的影响。  相似文献   

8.
蔡光义  马名杰  熊耀  邢康 《化学通报》2014,77(9):904-908
本文选取窑街油页岩和龙口油页岩作为研究对象,以正交实验为基础,采用HCl和HF脱除油页岩中的矿物质,得出在粒度0~0.2mm、HF浓度40%、浸泡时间5h、固液比1∶10的条件下两种油页岩脱矿物质率最大。采用红外光谱对脱矿物质前后油页岩和页岩灰的矿物质组成以及官能团结构变化进行分析,得到油页岩中矿物质主要有石英、高岭石和含铁矿物质等,酸洗能脱除绝大部分矿物质,但油页岩中的主要有机官能团变化不大,只有羧酸盐和含氧基团在脱矿物质后影响较大。  相似文献   

9.
木质纤维类生活垃圾热解过程矿物质和碳结构的演化规律   总被引:2,自引:0,他引:2  
使用水平管式炉,在不同热解温度(500~1 000 ℃)条件下对废纸屑和樟树叶两种木质纤维类生活垃圾进行了热解实验,分别采用X射线衍射(XRD)和拉曼光谱研究了样品所含矿物质和碳结构随热解温度的变化。结果表明,废纸屑和樟树叶含有的主要矿物分别为方解石和草酸钙,在500 ℃之前草酸钙全部转化为方解石,焦样中的方解石在800 ℃以后逐渐分解并形成生石灰。拉曼光谱对生活垃圾焦的碳结构变化非常敏感,低温热解时生活垃圾的大分子结构发生缩合和解聚,产生了孤立sp2碳原子,导致峰参数D1峰半高宽和峰面积比值ID1/IG逐渐增大;高温热解时晶体sp2碳原子增多,导致D1峰半高宽和ID1/IG逐渐减小。焦样的碳结构有序度随热解温度升高先降低后提高。  相似文献   

10.
利用固定床反应器研究了哈密煤温和液化固体产物(MLS)在热解过程中含硫气体的释放规律以及不同形态硫的变迁规律,并分析了矿物质对硫变迁规律的影响。结果表明,在实验考察的条件范围内,MLS热解过程中大部分的硫残留在半焦中,仅有不到10%的硫迁移到焦油中或转化为含硫气体逸出。热解生成的含硫气体以H2S为主,当热解温度为400℃时H2S的逸出速率达到最大。通过改进方法测定了MLS及其热解半焦中各种形态硫的含量,发现MLS热解过程中以硫化物硫和有机硫的分解和转化为主。随着热解温度的升高,MLS中有机硫逐渐分解并以含硫气体的形式逸出;当热解温度低于600℃时,MLS中硫化物硫逐渐转化为含硫气体、有机硫和少量的黄铁矿硫;当热解温度高于600℃时,MLS中碱性矿物质吸收气相中的H2S转化为硫化物硫,硫化物硫缓慢增加。醋酸酸洗可以保留MLS中大部分的硫化物硫,且酸洗后MLS热解生成的H2S逸出速率增大,峰温向低温方向移动;当热解温度高于600℃时,有机硫和硫化物硫的脱硫反应速率降低,并且MLS中的碱性矿物质与H2S反应生成金属硫化物,导致H2S逸出速率明显降低。  相似文献   

11.
采用电子顺磁共振(EPR)技术,系统地研究了热解温度对样品自由基浓度、g因子和线宽的影响。结果表明,油页岩干酪根及其制备的热解产物沥青、焦油和半焦的自由基浓度为2.29×1014-9.16×1014。当热解温度低于380℃时,主要发生干酪根的热解聚,当热解温度超过380℃,主要为中间产物热沥青的分解阶段,表现为热沥青的自由基浓度Ng和g因子值高于半焦。对EPR谱图线宽分析可知,当温度高于380℃时,焦油的线宽明显大于半焦和热沥青,说明液体内部自由基中自旋粒子间以及自旋粒子与环境的相互作用要比固体剧烈的多。温度低于380℃时,半焦和热沥青由于热解反应的进行,自由基自旋粒子之间及其与环境的相互作用增强,线宽随着温度的升高而增加。温度高于380℃时,半焦和热沥青的EPR曲线线宽降低,表明随着温度的升高自由基自旋粒子的相互作用减弱。  相似文献   

12.
In this study, the kerogen of oil shale from Moroccan Tarfaya deposits was isolated and the changes in the initial organic matter during the removal of the mineral matrix were examined. Chloroform extraction of the oil shale increases the intensity of the peaks in the X-ray diffractograms. Infrared spectra and X-ray diffractograms reveal the presence of mineral, calcite, quartz, kaolinite, and pyrite in the mineral matrix of the oil shale. Hydrochloric and hydrofluoric acids dissolution do not alter the organic matter. The nonisothermal weight loss measurements indicate that thermal decomposition of the isolated kerogen can be described by firstorder reaction. A single kinetic expression is valid over the temperature range of kerogen pyrolysis between 433K and 873K. Furthermore, the results indicate that the removal of mineral matter causes a decrease in the activation energies of the pyrolysis reactions of oil shale.  相似文献   

13.
Thermal behavior of green clay samples from Kunda and Arumetsa deposits (Estonia) as potential raw materials for production of ceramics and the influence of previously fired clay and hydrated oil shale ash additives on it were the objectives of this research. Two different ashes were used as additives: the electrostatic precipitator ash from the first field and the cyclone ash formed, respectively, at circulating fluidized bed combustion (temperatures 750–830 °C) and pulverized firing (temperatures 1,200–1,400 °C) of Estonian oil shale at Estonian Power Plant. The experiments on a Setaram Labsys Evo 1600 thermoanalyzer coupled with Pfeiffer OmniStar Mass Spectrometer by a heated transfer line were carried out under non-isothermal conditions up to 1,050 °C at the heating rate of 5 °C min?1 in an oxidizing atmosphere containing 79 % of Ar and 21 % of O2. Standard 100 µL Pt crucibles were used, the mass of samples was 50 ± 0.5 mg, and the gas flow 60 mL min?1. The results obtained indicate the complex character of transformations and show certain differences in the thermal behavior of Arumetsa and Kunda clays and their mixtures with oil shale ashes depending on the chemical and mineralogical composition of the clays as well as of the oil shale ashes studied.  相似文献   

14.
Specific features of the chemical structures of organic matter (Lerogen) in oil shales caused by the nature of the starting materials for the formation of shales and the routes of their subsequent alteration are reflected in the composition of shale semicoking (retorting) oil. In order to establish the analytical possibilities of the thermal decomposition method in elucidating the kerogen structure and to obtain more data on the mechanism of the pyrolysis of kerogens, the effect of a series of factors (rate of heating, pressure, presence of carrier gases, water and mineral matter of shale, treatment with reagents) on the yield and composition of the pyrolysis products of oil shales was investigated.The yield of shale oil and the phenol content in the latter increase when semicoking is performed in a stream of hydrogen at atmospheric pressure. In shale pyrolysis in the presence of water under pressure, the yield of oil and, in particular, water-soluble organic compounds also increase, as well as the content of neutral heteroatomic compounds in oil. With increasing content of mineral substances in shale, the yield of the semicoking oil (kerogen basis) and the content of polar compounds in it diminish owing to an increasing influence of oil adsorption on the mineral matter and its additional decomposition as a result.In the initial stage of thermal decomposition, both longer aliphatic substituents and side-chains of iso-structures split off and alkenes with a double bond in the middle of the chain (probably the products of elimination and dehydration of the aliphatic substituents with a hydroxyl group) are formed. The formation of n-1-alkenes, particularly those of even carbon number, which originate from the side-chains of odd carbon number by the cleavage of carbon–carbon bonds in the β-position to the cyclic nucleus of kerogen, becomes more pronounced in the final stage of pyrolysis when, owing to significant aromatization of the cyclic part of kerogen, the selectivity of the β-cleavage increases.  相似文献   

15.
The heating rate effect on the thermal behavior of clays from Arumetsa and Kunda deposits (Estonia) and an illitic clay from Füzérradvány (Hungary) was studied. Experiments were carried out under dynamic heating condition up to 1050 °C at the heating rates of 1.25, 2.5, 5 and 10 °C min?1 in a stream of gas mixture containing 79 % of Ar and 21 % of O2 with Setaram Labsys 1600 analyzer. Two different ashes were used as additives: the electrostatic precipitator ash from the first field and the cyclone ash formed, respectively, at circulating fluidized bed combustion (temperatures 750–830 °C) and pulverized firing (temperatures 1200–1400 °C) of Estonian oil shale at Estonian Power Plant. For calculation of kinetic parameters, the TG data were processed by the differential isoconversional Friedman method. The results of thermal analysis and the variation of the value of activation energy E along the reaction progress α indicated the complex character of decomposition of clays and their blends with Estonian oil shale ashes, and the certain differences in thermal behavior of different clays depending on their origin.  相似文献   

16.
The mineral reactions of Israeli oil shale fed to the GENESIS (Generation of Energy from Shale of Israel) split-stage fluidized-bed reactor have been studied by infrared. X-ray and chemical means. Organically bonded sulphur released during pyrolysis reacts with oxygen from the fluidizing air and with CaO resulting from decomposition of calcite to form CaSO4, mostly in a surface layer. At pyrolysis and coke-oxidation temperatures near 600°C, kaolinite reacts with calcite to form amorphous modified metakaolinite. At organic gas combustion temperatures near 1000°C, the amorphous phase in overhead fines reacts with additional calcite and quartz to yield gehlenite and larnite.  相似文献   

17.
The thermooxidative decomposition of four oil shale samples from Estonia, Jordan, Israel and Morocco and one sample of Estonian oil shale derivative, semicoke, was studied with the aim to determine the characteristics of the process and the differences of it related to the origin of oil shale. The experiments with a Setaram Setsys 1750 thermoanalyzer coupled to a Nicolet 380 FTIR Spectrometer were carried out under non-isothermal conditions up to 1000 °C at the heating rates of 1, 2, 5, 10 and 20 °C min−1 in an oxidizing atmosphere. A model-free kinetic analysis approach based on the differential isoconversional method of Friedman was used to calculate the kinetic parameters. The results of TG–DTA–FTIR analyses and the variation of activation energy E along the reaction progress α indicated the complex character of thermooxidative decomposition of oil shale and semicoke, being at that the most complicated for Estonian and Jordanian oil shale characterized by higher content of organic matter as compared to the other samples studied.  相似文献   

18.
在内构件(传热板和中心集气管)外热式固定床反应器中研究了油页岩热解产物生成特性,并与无内构件的相同常规固定床反应器内的油页岩热解行为对比,考察了两反应器中油页岩升温特性、热解产物分布、页岩油品质以及气体产物组成的变化规律.结果表明,内置传热板和中心集气管显著强化了反应器内的传热,相对于无内构件常规固定床反应器,料层升温速率提高了约2倍.对于依兰油页岩,其热解页岩油产率明显提高,最高达11.1 wt%(干燥基),明显高于无构件常规固定床反应器获得的页岩油产率.随着外加热炉温度的升高,内构件固定床反应器的页岩油产率逐渐增加,而无内构件常规固定床反应器的页岩油产率则明显降低.当外加热炉温度为1000℃时,前者页岩油产率是后者的2.3倍,并且内构件固定床反应器的热解水产率较低.两反应器中热解气产物组成相近,其H2与CH4之和占气体总量的70 vol%左右,热值为4406~5400 kcal/Nm3.  相似文献   

19.
Thermal analysis has been used to determine the impact of heating on the decomposition reaction of two Moroccan oil shales between ambient temperature and 500°C. During pyrolysis of raw oil shale, the residual organic matter (residual carbon) obtained for both shales depends on the heating rate (5 to 40°C min-1). Three stages characterize the overall process: the concentration of carbonaceous residue decreases with increase of heating rate, become stable around 12°C min-1 and continue to decrease at higher heating rates. Activation energies were determined using the Coats-Redfern method. Results show a change in the reaction mechanism at around 350°C. Below this temperature, the activation energy was 41.3 kJ mol-1 for the decomposition of Timahdit, and 40.5 kJ mol-1 for Tarfaya shale. Above this temperature the respective values are 64.3 and 61.3 kJ mol-1. The reactivity of Timahdit and Tarfaya oil shale residual carbon prepared at 12°C min-1 was subject to a dynamic air atmosphere to determine their thermal behaviour. Residual carbon obtained from Tarfaya oil shale is shown to be more reactive than that obtained from Timahdit oil shale. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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