油页岩炼制过程技术经济分析

我国油页岩资源储量大, 开发油页岩可以缓解我国石油短缺问题。但迄今少有研究对现有的油页岩炼制的能量利用情况和经济效益进行系统量化分析。本文以油页岩典型炼制工艺:抚顺炉工艺和瓦斯全循环炉工艺为案例, 对两种工艺建模和模拟, 根据模拟结果分析两种工艺物流和(火用)流情况, 分析单元中质量损失和(火用)损失的组成和主要因素。基于物流和能流对两种工艺进行经济性能分析。结果表明:以油页岩处理量为418t/h为基准规模, 抚顺炉工艺的(火用)损失比瓦斯全循环炉工艺的(火用)损失高出19.5%;经济方面, 瓦斯全循环炉工艺投资费用为16.9亿元, 较抚顺炉工艺的投资费用高5.1亿元, 但是瓦斯全循环炉工艺多生产5.4t/h页岩油和84.8MW电力, 所以其投资利润率为18.6%, 较后者提高了10个百分点。     

Composition and kinetics of oil generation from non-isothermal oil shale retorting

Oil shale retorting has been carried out under non-isothermal conditions between 623 and 773 K and at different pressures(78 and 765 kPa). The shale oil is separated into five individual components: polar, weak polar, saturates, aromatics and olefin, using a comprehensive analytical procedure. The effects of retorting pressure and heating rate have been studied. The oil yield under high pressure (765 kPa) is ≈10% less than the oil yield under ambient pressure (78 kPa). Much of this reduced yield can be accounted for by the reduced amount of polar component formed at high pressure. Heating rates of 1.67 × 10^?2, 6.67 × 10^?2and 8.33 × 10^?2Ks^?1 have been used; a higher heating rate causes a delay in the appearance of the oil. A simplified kinetic scheme is proposed which includes the distribution of liquid products and pressure effects. The activation energies and frequency factors of generation reactions for total oil and individual components have been obtained.     

气体热载体干馏炉内布气方式对油页岩干馏特性的影响

为研究炉内油页岩的干馏特性及炉内的温度分布,自行搭建处理量为5 kg/h的循环瓦斯热载体干馏试验装置,试验结果表明炉内布气方式对页岩的干馏特性具有很大影响。在边壁进气与中心管进气体积比为8∶4时油收率达到最大值,且炉内温度分布最均匀,单位时间内的放热量最大;不同的布气方式导致干馏层内气体冲刷页岩颗粒程度的不同,使得炉内油页岩的传热特性存在差异,炉内温度分布与放热量不同,最终油收率也不同。边壁进气在炉体内部的传热效果优于中心进气。温度分布越均匀,油收率越高;该布气方式依然存在局限,需要进一步研究。     

煤系共伴生油页岩热解残渣利用技术

油页岩残渣是油页岩热解过程中排放的固体废物,约占油页岩的80%~90%。中国油页岩残渣利用率较低,残渣堆积量日益增多,后续问题十分突出。煤系油页岩残渣的资源化利用成为油页岩热解提油产业发展的瓶颈。介绍了油页岩热解加工利用现状及其残渣在废水处理和废气吸附方面的应用,分析了当前页岩热解残渣利用过程中存在利用方式单一的问题,并结合油页岩热解残渣结构和组成的特殊性,提出了油页岩残渣用作环保材料如吸附剂的发展方向。     

Potassium catalysed gasification of Kentucky oil shale char

The steam gasification of a Kentucky oil shale char has been studied in a semi-batch fixed bed reactor. The effects of temperature (973–1173 K), catalyst loading (0–15% K₂CO₃) and pressure (up to 0.65 MPa) on the gasification rates and make-gas composition have been determined. Although gasification rates were increased by a factor of about three in the presence of 10% K₂CO₃, they were still significantly lower than those previously measured with western shale chars. The reason for this could be attributed to the relatively high hydrogen concentrations produced in the fixed-bed configuration since severe hydrogen inhibition has been previously reported for a similar shale char. There was no significant effect of the potassium catalysis on either the make-gas composition or the quantities of sulphur released during gasification. The only significant influence of pressure was to increase the methane make and this was independent of the catalyst loading.     

中国油页岩干馏技术现状与发展趋势

中国油页岩资源丰富,换算成页岩油储量高达476亿吨.目前中国页岩油生产企业仍然采用以抚顺炉为主的干馏技术,该技术成熟稳定,但油收率不高.本文介绍了目前国内已投产运行和即将工业化的干馏技术以及曾经投入生产、后因多种原因停产的干馏技术.分析表明,我国油页岩产业正处于技术快速发展和产业成长阶段:为显著提高油收率,针对抚顺炉的改进技术已有一些进展,自主研发的成大气体热载体干馏工艺已经开始商业化运行,我国自主知识产权的固体热载体干馏技术出现.但依然存在诸多问题:国内干馏炉单炉处理量小、油收率偏低、半焦无法利用等问题亟需解决,国内固体热载体干馏自主技术依然处于试验阶段,引进国外先进的干馏技术尚没有实质性进展,国内页岩油回收技术亟待改进,油洗技术亟需完善和推广.     

基于Aspen Plus的桦甸式油页岩干馏工艺系统模拟

引言油页岩是一种富含有机质、具有微细层理、可燃烧的细粒沉积岩,油页岩作为能源资源,既可以干馏炼油也可以燃烧发电。油页岩储量丰富,截至2005年底,37个国家油页岩探明总储量折算     

干馏条件对油页岩半焦孔隙结构的影响

油页岩干馏过程中发生挥发分物质的析出,导致颗粒的孔隙结构发生重大的变化,进而会对油页岩半焦的燃烧反应、成灰等特性产生重要的影响。利用扫描电镜、氮气吸附/脱附法对不同干馏温度、不同干馏时间下制备得到的桦甸油页岩半焦进行了孔隙分析,并与前人针对相同样品的油页岩半焦燃烧特性实验研究进行了对照分析。结果表明,在实验范围内,随干馏温度增加,受热解二次反应产生的焦炭对孔隙堵塞的影响,油页岩半焦孔隙比表面积和比容积先增加后减小;随干馏时间增加,伴随着小孔之间的合并,油页岩半焦孔隙比表面积先增加后减小,比容积单调增加。     

油页岩低温干馏过程的Aspen Plus模拟

利用Aspen Plus系统流程模拟软件模拟油页岩的低温干馏,并按照含油率测定实验工况来设置系统流程,以探讨将Aspen Plus应用于油页岩热解领域的可行性。针对吉林地区桦甸一矿4层和二矿11层的油页岩试样进行模拟,并将所得的含油率、含水率、半焦产率、干馏气体产率及半焦中各元素含量等模拟数据与实验值进行对比分析,模拟结果与实测值间的误差均控制在合理范围之内。对比结果表明,系统流程的建模及物性参数设置是正确合理的,可为后期构建完整的油页岩综合利用系统提供参考。     

Enhancement of oil recovery in the combustion retorting of oil shale by the addition of coal

The effect of coal addition in the combustion retorting of oil shale has been studied for various flow rates of air and grades of oil shale. The results indicate that oil yield is increased with coal addition, for example, by as much as 40% with 4 wt.% of coal in the retorting of 0.059 dm³/kg (14 gallons per short ton) oil shale. The distance between the combustion and the retorting zone is separated farther with the addition of coal. This makes it possible to operate the combustion retorting process at an increased rate without an increased oil loss. It is thus possible to increase the oil yield as well as the rate of retorting with a relatively small addition of solid fuel.     

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。     

油页岩干馏技术影响因素及工业发展展望

对油页岩资源的分布及储量情况、油页岩干馏过程及其影响因素、国内外的油页岩干馏技术及其工业发展现状进行了介绍,并对油页岩干馏工业进行了展望。     

油页岩过热蒸汽的干燥动力学

以油页岩颗粒作为干燥物料,以过热蒸汽和热空气分别作为干燥介质,进行了油页岩干燥实验的研究。当颗粒粒径减小时,油页岩干燥速率越大;过热蒸汽和热空气温度增大时,干燥速率也越大。对比相同条件下过热蒸汽和热空气干燥油页岩的平均干燥速率,发现当干燥介质温度超过逆转点温度时,过热蒸汽条件下的平均干燥速率大于热空气下的数值。实验得出粒径分别为9,7,5 mm的油页岩颗粒逆转点温度值分别是154,179,177℃;逆转点温度值是个变量,随颗粒粒径大小变化而变化。颗粒粒径越大时逆转点温度值越小,粒径较小时逆转点变化不大。采用薄层干燥模型对油页岩的干燥数据进行动力学模拟,可得修正Page模型(Ⅱ)干基水分比w模拟值与实验值的最大绝对偏差是12%,综合比较发现修正Page模型(Ⅱ)能较好地描述油页岩在过热蒸汽条件下的干燥过程。     

基于Aspen Plus抚顺式油页岩干馏工艺数值模拟

在Aspen Plus平台上建立了抚顺式油页岩干馏工艺模型,利用Aspen Plus的灵敏分析模块研究了抚顺炉气化段温度对产气组分的影响、空气/水蒸汽质量流率比值对产气组分和产气热值的影响,以及干馏段温度对收油率的影响,模拟结果与实际数据吻合良好。结果表明,抚顺炉气化段温度在650～750℃反应最为剧烈,生成的气体量收益最好。随着空气/水蒸汽质量流率比的逐渐增加,CH4和CO2量逐渐减少,CO、H2和N2量逐渐增加,热值也随之降低。干馏段温度在550℃时,收油率达到6.85%,可作为干馏炉热解段的最佳运行温度。     

Results of mathematical modeling of oil shale retorting in an aboveground,internal combustion retort

The one-dimensional mathematical model developed at the Lawrence Livermore National Laboratory to simulate the detailed chemical reaction kinetics involved in modified in-situ retorting of oil shale has been applied to simulate aboveground retorting in a moving, packed-bed retort. Application of the model to simulate such a retort was made for the internal combustion mode of operation, using typical operating conditions of the Paraho semiworks retort. Comparison with the semiworks experimental data revealed the general accuracy of the model in calculating retort temperature profiles, oil yield, off-gas composition, and outlet shale composition. The model was also applied to a hypothetical set of commercial-scale conditions in order to identify key operating or design parameters. These parameter studies predicted that the oil yield and the overall process performance could be markedly improved by increasing the recycle gas flux, decreasing the inlet-air flux, and relocating the inlet-air distributors. A process flowsheet was developed for the complete retorting system.     

Structural and quantitative evolution of organic matters in oil shale during two different retorting processes

In this study, traditional strongly endothermic anaerobic retorting (AR) and relatively novel self-heating retorting (SHR) processes for oil shale (OS) were investigated and compared in detail. These studies mainly involve the structural and quantitative evolution of organic matters in OS during retorting, including varieties of crystallite parameters, carbon framework structure, amounts of various structural carbons and toxic polycyclic aromatic hydrocarbons, and so on. The obtained results well elucidate some reaction pathways in AR and SHR as well as certain differences between the two retorting processes. Moreover, based on our former work that verifies SHR greatly simplifies retorting operation by in situ generating heat to replace external heat carrier/provision, this study further demonstrates that SHR also alleviates the environmental effect of organic toxic residues as compared to AR. The present study provides some critical results not only for penetrating the reaction mechanism but also for assessing or controlling the environmental impact of both retorting processes.     

油页岩含氧低温载气干馏过程实验

油页岩干馏生产页岩油是油页岩的主要加工利用方式。为降低油页岩干馏所需热载气温度,以延长载气预热器使用寿命并实现节能操作,本文向热载气中掺入一定比例氧气,对含氧低温载气情况下的油页岩干馏过程进行了研究。测定了油页岩在含氧气体氛围中热解时的反应器床层升温特性,对气液相产物组成进行了分析并与无氧干馏产物进行了比较。结果表明,含氧低温载气干馏过程能够通过载气中的氧气与油页岩反应产生的热量使油页岩达到其干馏所需要的温度,页岩油收率及其成分与无氧高温载气干馏过程接近、而轻组分含量更高,并且含有更多的具有O—H键和C==O键官能团的化合物。本文研究结果为油页岩干馏生产页岩油提供了一种新的技术方法,具有较好的工业应用前景。     

油页岩与固体热载体在回转干馏炉内混合特性的冷态实验

实验研究了回转干馏炉内非等粒径油页岩与固体热载体颗粒群的混合行为,以回转干馏炉出口油页岩质量分数的样本变异系数作为混合指数。对2种填充率、2种抄板形式、2种倾角在5种转速的不同工况下出口的混合指数进行计算,对比分析了混合指数的变化趋势及不同影响因素的混合机理,得出20%填充率采用直角抄板在倾角为3.24°时混合度优于其它对应工况,以对流混合为主。     

Results of mathematical modeling of oil shale retorting in an aboveground,external-combustion,moving-bed retort

Our one-dimensional mathematical model for simulating the chemical reactions and physical processes in oil shale retorting was applied to the indirect mode of operating an aboveground retort in which externally heated recycle gas provides the heat required for the retorting process. Countercurrent to the hot gas flow, a moving bed of shale is pushed upward through an expanding conical reactor, as in the Union B retort. The model was applied to a hypothetical set of commercial-scale conditions in order to identify key operating or design parameters. Variations in recycle-gas temperature and flow rate, shale flow rate, shale grade, water content, particle size distribution, bed porosity, uniformity of bed porosity, and retort dimensions were studied. The results of these calculations help identify the relative importance of the different process parameters in terms of oil yield, pressure drop, exit temperature of gas and shale, fuel consumed in heating the recycle gas, compressor power, condenser cooling load, and reactor size.