油页岩颗粒的热解模型

以实验为依据,分析了油页岩的热解机理及特性,并充分考虑了油页岩中挥发分在整个热解过程的作用,在此基础上建立了与油页岩固有热解特性相适应的热解模型。在能量方程中考虑了油页岩挥发分的热解反应吸热量及其挥发分的释放对油页岩固体颗粒质量的影响,并根据油页岩的热解特性,采用分阶段模型来描述油页岩的热解过程,以减小一步本征动力学方程带来的较大误差,还对模型进行了实验验证。     

Pyrolysis of Tertiary oil shale by a dolerite intrusion,Stuart Deposit,Queensland, Australia

The mid to late Eocene oil shale sequence of the Stuart Deposit, eastern Queensland, Australia, has been intruded by an alkali dolerite laccolith. The dolerite pyrolysed the intruded sediments with the observed aureole up to 68 m thick. Petrographic studies of samples from five drill holes that intersected the aureole showed that vitrinite reflectance near the top of the aureole generally decreases with depth but closer to the contact vitrinite reflectance rapidly increases. The lowest reflectance values are associated with a zone of bitumen, derived from the thermal alteration of alginite, in each of the five drill holes. The decrease in vitrinite reflectance is accompanied by a decrease in the fluorescence intensity of alginite and a shift in fluorescence colour towards the red end of the spectrum. In the zone characterized by the rapid increase in vitrinite reflectance, the alginite was pyrolysed and pyrolytic carbon formed.     

Pyrolysis kinetics for Green River oil shale from the saline zone

The nature of the organic and mineral reactions during the pyrolysis of Saline-zone Colorado oil shale containing large amounts of nahcolite and dawsonite has been determined. Results reported include a material-balanced Fischer assay and measurements of gas evolution rate of CH₄, C₂H_x, H₂, CO and CO₂, Stoichiometry and kinetics of the organic pyrolysis reactions are similar to oil shale from the Mahogany zone. X-ray diffraction and thermogravimetric analysis results are used to help determine the characteristics of the mineral reactions. Kinetic expressions are reported for dawsonite decomposition, and it is demonstrated that the temperature of dolomite decomposition is substantially lower than for Mahogany-zone shale because of the presence of the sodium minerals.     

Pyrolysis with partial combustion of oil shale fines in a spouted bed

Pyrolysis with partial combustion of oil shale fines from the Irati Formation in Brazil has been investigated in a 30 cm diameter spouted bed reactor. Experiments were carried out at atmospheric pressure and temperatures between 450 and 600°C. The oi] shale particle size was less than 6.35 mm. Spouting gas temperatures ranged from 20 to 565°C. Three inlet gas pipe diameters and two spouted bed heights were studied. Operation of the process was found to be stable over a wide range of test conditions. Results are presented for oil and gas quality, efficiency of retorting and overall performance of the plant.     

美国绿河油页岩中沥青热解特征及动力学

沥青是油页岩中的重要有机质,也是油页岩中油母质热解产油和气过程的重要中间产物,对其热解研究有利于加深油页岩/油母质热解理解。通过索氏萃取提取出了绿河油页岩中的沥青,并对其进行了不同升温速率下热解实验。基于热重（TGA）数据,使用Friedman法计算了沥青热解的活化能,并通过活化能分布特征,推测沥青热解可能包含三个过程。接着,使用双高斯函数对含有交叠峰的DTG曲线进行反褶积处理,分解成三个峰,依次对应每一个过程。使用最小二乘法获得了这三个过程的活化能、指前因子和反应模型通式,并将获得的通式与四类固态物质热解模型中的11种理想模型进行对比,辨识出上述三个过程均遵循n级反应模型。     

油页岩热解的FG-DVC模型

为研究油页岩结构与热解反应性之间的关系,在TG-FTIR分析仪上对甘肃油页岩在不同升温速率条件下（5、20、50℃·min^-1）进行了热解实验研究,对CH₄、CO、CO₂、H₂O和页岩油进行了定量分析,并采用非线性最小二乘拟合方法求解各组分析出的动力学参数,同时采用基于燃料化学结构的FG-DVC模型对各组分的析出过程进行了模拟。结果表明：油页岩的脱挥发分过程主要发生在200～600℃之间;油页岩中有机质所含官能团以脂肪烃为主;由于各官能团活性不同,导致气态产物的析出有先后顺序;由非线性最小二乘拟合方法获得的各种产物析出的活化能E分布在188～239 kJ·mol^-1之间,而指前因子A在10⁹～10¹³ s^-1之间;各产物的FG-DVC模拟结果与实验数据较为相符,这说明用FG-DVC模型来描述甘肃油页岩的热解脱挥发分过程是比较合适的。     

Determination of polar compounds in Rundle shale oil

The acidic and basic components of three distillate fractions (light, middle and heavy) of shale oil from the Rundle (Queensland, Australia) deposit were selectively extracted. Capillary gas chromatography/mass spectrometry was used to identify individual polar components. The major nitrogen-containing polar compounds in the light fraction were alkyl-substituted pyridines, and substituted quinolines were more abundant in the middle and heavy fractions. Significant quantities of pyrrole derivatives were also identified. Small quantities of anilines and benzoquinolines made up the remainder of the bases. The oxygen-containing compounds were mainly phenolic in nature; alkyl-substituted phenols were the major components, but significant quantities of naphthols and traces of fluorenols were identified.     

油页岩半焦热解特性

利用热重分析仪对油页岩半焦热解特性进行了研究.综合考虑制取半焦所获得的页岩油品质、半焦成分、发热量和循环流化床设计,认为干馏温度介于500～600℃为宜;干馏度对半焦热解初析温度和低温段热解过程有影响,但对高温段热解影响不明显,高温干馏所制取的半焦其热解过程包含于低温所制取的半焦热解过程中;随升温速率的提高,相同温度下的半焦热解度降低,当升温速率超过40℃•min^-1后,升温速率对半焦热解过程影响不大;最后采用Coasts法计算了油页岩半焦热解动力学参数,计算结果可供数值仿真和工程设计参考.     

小颗粒窑街油页岩流化床热解提油特性研究

在电炉加热流化床热解反应器上,进行了小颗粒窑街油页岩热解提油实验,研究了热解温度和固相停留时间对热解提油特性的影响,并深入分析比较不同条件制得焦油的品质。结果表明:热解反应进程、固液气三态产物分布和焦油品质主要受热解温度影响,受固相停留时间的影响相对较小。在500—600℃范围内,随着热解温度上升,热解反应从热分解阶段过渡到热缩聚阶段,液体产率和焦油品质均先上升后下降、并在550℃均达到最佳,此时液体产率为6.5%,一级热解液体产物中焦油的饱和分和芳香分质量分数分别达到30.0%和29.4%。在15—45min的固相停留时间范围内,适当延长固相停留时间有利于物料中可热解成分的析出,液体产率增大,焦油含中低温馏分及饱和分和芳香分的质量分数先增大、30 min后基本不变。     

油页岩热解特性及其甲烷释放规律研究

为研究油页岩热解特性及热解过程中甲烷的释放规律,采用热重-傅里叶变换红外光谱（TG-FTIR）对龙口（LK）、内蒙（NM）、汪清（WQ）三个地区的典型油页岩进行热解实验,并结合固相红外（FTIR）对油页岩的官能团结构进行分析。研究结果表明,油页岩热解过程可分为四个阶段,热解反应及挥发分释放主要发生在第二阶段（400～600℃）。甲烷的析出与油页岩结构中的脂肪烃（光谱范围3000～2800 cm^-1）密切相关,脂肪烃含量越多,热解过程中释放的甲烷越多。通过对甲烷析出曲线分峰拟合及结合动力学分析,得出甲烷的生成是由一个脱吸附过程和四个化学反应共同作用的结果。     

Pyrolysis behaviour of Australian oil shales in a fluidized bed reactor and in a material balance modified Fischer assay retort

The pyrolysis behaviour of several Australian oil shales was determined using the material balance modified Fischer assay and a bench-scale fluidized bed pyrolysis reactor, with nitrogen or steam as the sweep gas. The assay oil yield, which ranged from 5.3 to 15.7 wt% of the dry shale, did not correlate well with the organic carbon contents of the shales. However, under both assay and fluidized bed pyrolysis conditions, a shale of high kerogen H/C had high organic carbon conversions to oil. Compared with the Fischer assay, nitrogen pyrolysis gave 7 ± 4 wt% more oil for the shales studied, and steam pyrolysis gave 15 ± 4 wt% more oil for all shales except one, which showed a 35 wt% increase in oil yield. However, the oils from both nitrogen and steam pyrolysis had lower H/Cs, higher sulphur and nitrogen contents, and more high boiling point fractions than those from the Fischer assay. Nitrogen pyrolysis oils were of higher quality than those produced by steam pyrolysis. With steam as the sweep gas, much more hydrogen and hydrogen sulphide were produced for all shales; in most cases, there was also more carbon monoxide and less hydrocarbon gases.     

Selective removal of nitrogen compounds from shale oil

A solid extraction process for selectively removing nitrogen from alternative refinery feedstock has been developed. It has been demonstrated that solid CuCl₂ · xH₂O can reduce the nitrogen content of shale oils to acceptable levels for some refineries. In a simple single-stage process, the nitrogen content was reduced by more than 85% to levels below 0.2 wt%. The solid extraction process was remarkably selective and produced high oil recovery yields corresponding to ≈98% of the theoretical limit. Experiments with model systems have shown complete selectivity for the nitrogen compounds and have demonstrated that the entire bulk of the solid is involved in the extraction process. Many other solids have been shown to be effective, namely transition metal halides, nitrates, sulphates, acetates, fluoroborates, and phosphates.     

Effect of lignite addition and steam on the pyrolysis of Turkish oil shales

Steam was found to be a more effective sweep gas than nitrogen at low velocities in fixed-bed pyrolysis of Goynuk oil shale but, at higher velocities and in fluidized-bed pyrolysis, the differences were considerably less marked. Relatively small but significant synergistic effects were observed between lignites and the two oil shales investigated — Goynuk and Seyitomer — under static retorting conditions. These effects were more pronounced with large concentrations of oil shales but disappeared in fluidized-bed pyrolysis, where conversions are considerably higher because mass transfer limitations largely disappear.     

Gas evolution during pyrolysis of various Colorado oil shales

Rates of evolution of C0₂, CO, H₂, CH₄ and the C₂ and C₃ hydrocarbons during the pyrolysis of seven Colorado oil shales have been measured. These shales, which are from various depths at two different sites, yield 34–255 ¦ of oil per tonne raw shale (9–61 US gal of oil per short ton raw shale) and linear heating at a rate of 2°C min⁻¹ was used for the retorting of all samples. The objective of the study is to monitor variations in gas evolution from shales of different organic content and from various stratigraphic and areal locations. Comparisons between shales from each site are made together with correlations with data from Fischer assays. A kerogen concentrate (mineral fraction removed by HCl-HF treatment) and retorted shale from a Fischer assay are also included. The ability of a kinetic model due to Campbell et al. to predict gas evolution is tested and it is found necessary to modify slightly some of the stoichiometric coefficients to obtain good agreement. The resultant kinetic model should adequately describe the gas and oil evolution behaviour of shale from the upper portion of the Green River formation.     

Rapid pyrolysis of brown coal and oil shale

A brown coal, peat and oil shale were subjected to a rapid pyrolysis process and medium-heat-value gases together with tar were collected. The char residue was of high activity and suitable for gasification to create a two-stage gasification system. The coal-tar is used for manufacturing liquid fuels and chemicals.     

Pyrolysis/g.c. of oil shales and coal

Pyrolysis studies of coal, kerogen and oil shales were carried out in a microprobe connected to a gas Chromatograph, in the temperature range 620–1160 °C. It was shown that the CO₂ evolved in the decomposition of the carbonates in the shales participates in the reaction and complete volatilization of the organic matter takes place. The product distribution can also be changed by the use of a nickel catalyst in the pyrolytic tube.     

利用GC-MS与NMR技术研究干馏终温对桦甸页岩油组成性质的影响

通过控制桦甸油页岩干馏终温,得到5个不同终温下页岩油样品,对各页岩油样按沸点300℃进行切割,其中轻质油馏分(<300℃)进行GC-MS检测,对产物分类统计,分析页岩油组成成分随干馏终温变化规律;重质油馏分(>300℃)进行了¹H和¹³C核磁共振波谱分析,对谱图积分获得其氢、碳分布情况,研究了干馏终温对页岩油化学结构的影响。结果显示,轻质油组成中脂肪族化合物占绝大部分,其中正构烷烃、α-烯烃和正构醛、醇三者具有同源性,均由烷基自由基生成。随着干馏终温的升高,长链烷烃分解,支链烷烃侧链断裂,使轻质油脂肪烃碳链长度变短,重质油直链脂肪烃增多,页岩油发生更多的芳环缩合反应导致轻质油与重质油芳香环数量均增多,同时轻质油中芳环缩合程度加深。     

固有碳酸盐和硅酸盐对太姥油页岩热解产物的影响

通过逐级酸洗脱除新疆太姥油页岩中的碳酸盐和硅酸盐矿物,采用铝甑炉对油页岩原样和脱矿样进行热解,分析油气产物的组成性质,基于产物产率和性质考察了固有矿物质对油页岩热解的影响。结果表明,碳酸盐能促进热解生油,且使页岩油中含氮、氧化合物含量增大,硅酸盐则抑制热解生油,并抑制含氧化合物的生成,二者均使页岩油的H/C降低。硅酸盐可促进烷基自由基与氢自由基的结合,使页岩油中烷烃含量升高、烯烃含量降低,且使H₂产率减小,并能催化长链脂肪烃的裂解,使页岩油中长链烃含量降低、短链烃含量升高,且使烃类气体产率增大,而碳酸盐则抑制自由基的结合和长链脂肪烃的裂解。     

Isothermal oil shale pyrolysis. 1. Oil generation and composition at various pressures

A rich (250 I (59 gal) per ton) Green River oil shale was retorted in a helium atmosphere. Isothermal retort experiments from 375 to 500 °C were carried out at 78 kPa and 765 kPa. Oil was collected as a function of time and a comprehensive analytical procedure was developed and utilized to determine seven oil fractions: straight-chain pentane de-asphaltened dry whole oil (DDWO); solids; saturates (S); aromatics (A); olefins (0); ‘weak’ polars (WP); and polars (P). The objectives of this work were: (a) to develop data to show oil generation and composition at different temperatures and pressures under isothermal, isobaric conditions; (b) to determine the effect of pressure on total oil yield and product-oil composition. Total oil yield was reduced as the pressure was increased. Much of this reduction can be accounted for in the reduced amounts of polar compounds formed at higher pressure because the polar fraction comprises approximately 35–45 wt% of the DDWO. In general, the amounts of aromatics present increase, the amounts of olefins decrease, and the amounts of saturates and ‘weak’ polar compounds remain relatively constant with increased system pressure.