原油及重油的快速分析技术进展

近年来,随着我国原油加工量的不断增加,加工难度的不断增大,原油快速评价问题日益受到重视.原油评价是指在全面分析原油的物理及化学性质的基础上,对原油的可加工性能及加工过程中可能出现的问题进行综合分析的过程.目前飞速发展的计算机技术及仪器分析技术,为原油快评技术奠定了良好的基础.该文以不同分析方法进行分类,介绍了近红外光谱(NIR)、中红外光谱(IR)、核磁共振波谱(NMR)及其他分析方法在原油和重油快速分析领域的技术进展.     

基于石油烃特征比值的多元统计方法进行原油鉴别

基于原油中有生源意义的生物标志物及原油特征多环芳烃的特征比值,采用主成分分析和聚类分析法,对渤海3个不同区块的4种原油,以及其中1种原油风化7d、15d和30d的风化油样和陆地油田1和陆地油田2各1种原油进行鉴别。结果显示:利用主成分分析和聚类分析可以实现大量油样的快速分类鉴别,不仅可以对差异较大的原油进行区分,还可以对原始原油及其风化原油进行很好分辨,但对差异较小的原油,两种分析方法的分辨能力仍有一定局限性。     

触变性含蜡原油等温胶凝过程特性及模型研究

综合利用理论推导和流变实验方法对触变性含蜡原油的等温胶凝过程进行了详细的研究, 采用结构参数法建立了静态结构恢复模型, 并经实验结果证明该模型对多种原油的结构变化曲线均有较高的拟合精度. 同时以青海原油为例, 根据实验数据和拟合参数分析了含蜡原油等温胶凝过程特性. 结果表明, 随着温度的升高、预剪切速率的增大以及预剪切时间的增加, 原油在恒温静止过程中形成的结构强度均会减弱. 测量温度越高, 预剪切时间越长, 则原油的结构参数变化速率越大; 而预剪切速率越高, 原油结构参数变化速率在初始阶段越大, 在最终阶段反而越小, 但与未经剪切油样相比, 原油受剪切后其结构参数变化速率在整个测量时间范围内均偏大.     

原油中双环倍半萜指纹的内标法分析

采用气相色谱-质谱联用(GC-MS)技术,建立了原油中双环倍半萜化合物内标法半定量的分析方法,确定了基于谱图特征、确认离子m/z 123、179、193、207及计算保留指数的组分定性方法,对10种双环倍半萜化合物进行了定性、定量分析.对不同地理位置海上油井平台9个原油的双环倍半萜指纹进行了分析.研究结果表明:原油中双环倍半萜化合物总含量在600～8000μg/g之间;各原油中均以4,4,8,9,9-五甲基十氢化萘(BS3)、4,4,8,9,9-五甲基十氢化萘(BS4)、C16-sesquiterpane(BS8)、8β(H)-升补身烷(BS10)化合物的含量较高,占双环倍半萜总量的60％以上;不同地理位置的原油中双环倍半萜含量的分布规律为:涠洲岛海区＞渤海海区＞进口原油G1、G2;国外原油G3的双环倍半萜含量与渤海原油B3的含量相当,但分布形式不同.同一区块不同采油平台原油中的双环倍半萜指纹非常相似,不同来源的原油中双环倍半萜化合物的分布特征及含量有很大的差异.通过此方法可以实现不同来源原油的准确鉴别.     

碳稳定同位素比质谱法对中东原油的鉴别

采用气相色谱/稳定同位素比质谱法(GC/IRMS)对具有相似化学特征的科威特、阿联酋、沙特以及伊拉克产的原油中正构烷烃(n-C10～n-C24)的碳稳定同位素比δ(13C/12C)进行了分析,通过原油单体烃分布趋势对比、主成分归类、同位素比值与诊断比例(Diagnostic ratio,DR)联用等方法对4种原油进行了鉴别。结果表明,沙特与伊拉克所产原油、科威特与阿联酋所产原油的单体烃分布趋势相似,且主成分相近,采用同位素比值与诊断比例联用法成功地对它们进行溯源。结果表明,沙特与伊拉克所产原油的δ(13C/12C)值以及DR(n-C17/pristane(Pr)、n-C18/phytane(Ph)、Pr/Ph)相近,说明它们具有相同的母质类型及沉积环境,属于同一种原油;科威特与阿联酋所产原油的δ(13C/12C)值相似,而DR明显不同,表明其母质类型及成熟度不同,属于不同种原油。本研究所采用的分析技术也适用于其它原油的溯源研究。     

辽河超稠原油的流变性质及其乳化降粘

研究了辽河超稠原油在不同温度下的流变性质，进行了辽河超稠原油的乳化降粘试验，研制出比较适宜的乳化降粘剂BHJ，制备出稳定性好、粘度适中的水包油型超稠原油乳状液。在乳化剂加量为6‰－1％的情况下，最大降粘率达到90％以上。并对超稠原油乳状液的流变性质、微观结构及燃烧特性进行了初步探讨。     

改进的广义回归神经网络用于基于气相色谱法的原油密度定量分析

在油气勘探开发领域,快速识别储集层原油性质对于工程技术人员有非常重要的指导意义.地球化学录井技术是用于判断储集层原油性质的常规手段,能为储集层综合评价提供专业认识.该文研究了地化录井中的岩石热解分析和气相色谱分析的原理,提出了一种利用色谱谱图对原油密度进行定量分析的新方法,再结合原油性质密度划分标准,可快速判断储集层原...     

原油烃指纹GC法在三元复合驱油井分层产能测试中的应用

通过三元复合液与水驱原油作用实验认为,三元复合液对原油烃指纹影响小;通过分层原油配比实验及测试与MFE法分层测试结果对比认为,两种测试方法具有很好的一致性,原油烃指纹色谱测试法适用于三元复合驱油井,为三元复合驱油井分层产能测试及驱油效果监测提供了有效的方法。     

微波消解-高分辨电感耦合等离子体质谱(HR-ICP-MS)法测定原油中22种微量元素

准确测定原油中微量元素含量,对研究原油地球化学,揭示原油原产地信息,具有重要意义。本文采用HNO3微波消解原油样品,优化了样品质量、消解试剂、消解程序等微波消解条件,研究了原油中B、Mg、Al、P、Ti、Ca、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、Ga、As、Sr、Mo、Cd、Sn、Ba、Pb共22种微量元素在低、中、高分辨率下的质谱干扰及校正方法,采用高分辨测定Ca,中分辨测定P、V、Cr、Mn、Fe、Ni、Cu、Cd、Co、Sr,低分辨率模式测定其余元素,建立微波消解-高分辨电感耦合等离子体质谱测定原油22种元素的方法。在优化的实验条件下,22种元素的线性相关系数均大于0.999,方法检出限为0.0002μg/g~0.07μg/g。选择原油多元素均质标准品（ConostanS-21）进行方法验证,B、Mg、Al、P、Ti、Ca、V、Cr、Mn、Fe、Ni、Cu、Zn、Mo、Cd、Sn、Ba、Pb元素测定结果的相对标准偏差为0.20%~2.80%,测定值与标准值基本一致;选择巴西原油、安哥拉原油、喀麦隆原油、尼日利亚原油进行Co、Ga、As、Sr元素加标回收试验,加标回收率为95.3%~104.3%,测定结果的相对标准偏差为0.2%~2.3%。选取巴西原油、安哥拉原油、喀麦隆原油、尼日利亚原油进行22种元素测定,分析了不同产地原油的元素含量差异。本方法能够应用于原油中多种微量元素的同时测定,灵敏度高,选择性好,检出限低,结果准确可靠,可为原油地球化学研究提供技术支持。     

降凝剂与原油组分相互作用的影响因素及降凝剂发展

概述了含蜡原油中的蜡、胶质、沥青质、轻烃等有关组分与降凝剂的相互作用特点，及其对原油改性效果的影响。并结合降凝剂的改性原理，对降凝剂的发展进行了介绍。     

Rheological properties of ethylene-propylene-diene elastomers

The processing of rubbers comprises a combination of complicated processes which realization almost always requires knowledge of their rheological behavior. The goal of the present work is to describe the rheological behavior of the EPDM vulcanizates via rotational rheometry. The effect of the cross-linking density and plasticizer content on the rheological behavior of the EPDM vulcanizates is described. The viscoelastic characteristics of the samples are defined from the frequency dependences of elasticity modulus G' and loss modulus G".     

Rheological Properties of Particle-Stabilized Emulsions

We have studied the rheological properties of fumed silica particle-stabilized emulsions. Two particles of different polarity were considered, the first more hydrophilic “Aerosil R7200,” the second more hydrophobic “Aerosil R972.” These particles flocculate and probably form a network at the investigated concentration. The flow curves of emulsions stabilized by a single type of particles exhibit yield stress, shear-thinning behavior and thixotropy. Moreover they display rheological features typical of gels. These features are attributed to strengthening of the particle network by droplets. Moreover the rheological properties of w/o emulsions stabilized by hydrophobic are similar to the ones of o/w emulsions stabilized by hydrophilic particles. The rheological properties of o/w emulsions stabilized by mixtures of hydrophilic and hydrophobic particles have then been studied by keeping the total particle concentration constant and varying the mass ratio between particles. The results show that when the hydrophobic particle concentration increases, the viscosity and stability of emulsions decrease establishing evidence that the network is weakened due to preferential orientation of hydrophobic particles towards the oil phase.     

Rheological Behavior Investigation of Concentrated Coal-Water Suspension

The Haake rheometer is used to determine the rheological property of coal-water suspension (CWS) made up from Datong coal, and the obtained rheological curves are fitted using power-law, Binghamplastic, Herschel-Bulkley, Casson, and Sisko models, respectively. The fitted parameters indicate that the Herschel-Bulkley model has the maximum correlation coefficient of all the rheological models, so the Herschel-Bulkley model is selected to study the rheological property of the prepared CWS. By means of the Herschel-Bulkley model, the effects of coal concentration, dispersant dosage and electrolyte addition on rheological property of CWS are studied. The results show that CWS with higher coal concentration tend to be pseudoplastic behavior, and CWS prepared using excessive dispersant show shear-thickening flow characteristic. The addition of high-valence cationic electrolyte increase the yield value and the pseudoplastic behavior of CWS, while the addition of anionic adjusting agent decrease the yield value of CWS, and the CWS tend to be shear-thickening flow characteristic.     

支化聚合物的熔体流变特性

从支化聚合物的流变特性表征以及分子结构和温度对其流变行为的影响三个方面综述了支化聚合物的流变特性，长链支化结构明显延缓了整个高分子的松驰过程，这集中表现在剪切条件下的应变软化和拉伸条件下的应变硬化，而且，长链支化使得时－温等效原理不再有效，对温度的依赖性也表现出一定的复杂性，改进蛇行理论和耦合模型可以解释部分实验结果，但又都存在不足，因此，对于支化聚合物独特的流变行为，还需进一步的深入研究。     

水性丙烯酸酯共聚物交联体系的流变性

用旋转粘度计研究了甲基丙烯酸甲酯／丙烯酸丁酯／丙烯酸三元共聚物水性交联体系的流变性，考察了树脂含量、金属鳌合物含量和氨水水化对其流变性的影响。结果表明：三元共聚物水性交联体系呈非牛顿流体流变行为，具有剪切变稀特性；随树脂含量或鳌合物含量增加，体系的增稠能力得以增强；水化不仅可改善体系的增稠性能，而且可增强体系的非牛顿流变性。     

Rheological Properties of Gels of Gelatin with Sodium Alginate

Effect of anionic polysaccharide, sodium alginate, on the rheological characteristics of gelatin gels is studied. It follows from the rheological curves that low-temperature gelatin gels with sodium alginate can be classified with elastoviscoplastic systems. Multicomponent gels obtained with the two gel-forming agents demonstrate synergism of the rheological characteristics.     

Rheological Equations for Concentrated Suspensions

The dependence of viscosity on stress in stable concentrated suspension is studied, the physical meaning of rheological constants in the rheological equation for these suspensions is revealed, and a method for experimental determination of these constants is described.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 2, 2005, pp. 219–223.Original Russian Text Copyright © 2005 by Bibik.     

Rheological behavior of fermentation broths in antibiotic industry

An experimental study of rheological behavior of three morphological types of fermentation broths in relation to process conditions was carried out in industrial and pilot-plant bioreactors. Three industrially manufactured antibiotic broths were studied: Cephalosporin C (fungal), tylosin (actinomycetic), and apramycin (proactinomycetic), in which the rheology may cause real problems. A viscometer with coaxial cylinders and six-blade impeller was used for rheological measurements. The shear rates range in which both the instruments give similar results was determined. During the experiments rheological and morphological behavior, pH, activity, biomass concentration, fats, glucose, and nitrogen concentrations were studied. All the broths studied exhibited nonNewtonian behavior, which could be described with Ostvald-de-Waele power-law model. It was found that the rheological behavior of the broths during the process is closely related to biomass concentration and morphological changes of mycelia, so that viscosity could be used as a parameter for process monitoring and regulation. A set of experiments on oxygentransfer improvement in the case of the most viscous tylosin broths by water addition was also done.     

Rheological properties of protein-surfactant based gels

Water-based protein-surfactant gels, formed by mixing bovine serum albumin (BSA) and sodium dodecyl sulfate in water, were investigated by rheological methods. The measurements were performed for many different protein-to-surfactant ratios as a function of the applied frequency, stress, or strain, as well as by changing the temperature, in the range between 15 and 65 degrees C. The rheological behavior of the gels as a function of applied frequency is interpreted in terms of the overlapping of at least two viscoelastic relaxation processes. The rheological results indicate the presence of thermal transitions from essentially viscous to mainly elastic regimes, in analogy with the thermal gelation processes observed in polymer solutions. The thermal gelation threshold in the present system is modulated by the protein/surfactant ratio. Differential scanning calorimetry measurements were also performed to determine whether thermal gelation is somehow concomitant to protein denaturation. The results indicate that the thermal denaturation of BSA in protein-surfactant based gels occurs at slightly higher temperatures than in the bulk. Scanning electron microscopy indicates the occurrence in the gel structure of globules formed by the arrangement of fibrils.