Rheology of Middle Distillate. I. Role of Composition

The rheological behavior of middle distillate (250-375°C) fraction, obtained from the waxy Bombay-High Off-shore crude oil, and its five narrow sub-fractions of 25°C interval each, i.e., Fr 1 (250-275°C), Fr 2 (275-300°C), Fr 3 (300-325°C), Fr 4 (325-350°C), and Fr 5 (350-375°C), have been studied below their ASTM pour point temperatures. The rheograms (the shear stress vs. rate of shear) of the fraction and sub-fractions, at various temperatures below their pour points, are recorded on a Haake RV-12 Co-axial Rota Viscometer fitted with a NV sensor and a temperature programmer (PG-20) and attached with a programmed heating/cooling system. From these rheograms the flow parameters like plastic viscosity, apparent viscosity, and yield stress are obtained and their variations with temperature and shear rate have been studied in terms of compositions of the fraction/sub-fractions. These results might be useful in devising methodology for overcoming the wax separation phenomenon from middle distillates at low temperatures.     

Effect of some prepared superplasticizers on the rheological properties of oil well cement slurries

Three superplasticizers namely: cyclohexanone glyoxylic sulfanilate (CGS), acetone glyoxylic sulfanilate (AGS) and melamine glyoxylic sulfanilate (MGS) were prepared and characterized using FT-IR. The prepared admixtures were evaluated as additives for improving the rheological properties of oil well cement. The effect of temperature (25°, 45° and 65?°C) and admixture dose (0.25, 0.5, 0.75 and 1%) were determined on the apparent viscosity, plastic viscosity and yield stress. The results showed that the prepared superplasticizers, CGS, AGS and MGS decreased these parameters. The results concluded that the CGS, AGS and MGS admixtures act as retarders and dispersant for oil well cement. The three prepared admixtures exhibited high enhancement on the rheological properties which mean that it can use in oil cementing processes.     

影响聚合物段塞流变性因素的研究

本文针对我国表面活性剂/聚合物驱油的实际,研究了石油磺酸盐(PS)、正丁醇(R_4OH)和矿化水对水解聚丙烯酰胺(HPAM)溶液流变性的影响。结果表明,PS对HPAM溶液流变性的影响与介质的矿化度有关:非矿化水介质中,PS对HPAM溶液性质的影响类似于无机盐,能降低HPAM溶液的表现粘度(η_α)和稠度系数(k);当系统中含有一定浓度矿化水时,PS却能升高系统的η_α和k值,降低流型指数(n),使系统的非牛顿性增强。在含有PS和矿化水的HPAM系统中加入R_4OH,系统的η_α和k值会有所增加。     

Stabilization Studies of Middle Distillate Fuels: Structural Composition of Insoluble by FTIR Spectroscopy

Abstract

For reducing the supply-demand gap of diesel fuel, blending of cracked stocks is essential with straight run products. This enhances the instability problem. This problem can be reduced using various stabilization procedures. In the present paper blends of cracked stocks light cycle oil (LCO) with straight run gas oil (SRGO) were stabilized by methanol extraction and hydrostabilization techniques. The insoluble from these fuels as such and their blends were stabilized and characterized using FTIR spectroscopy.     

Stabilization Studies of Middle Distillate Fuels: Structural Composition of Insoluble by FTIR Spectroscopy

For reducing the supply-demand gap of diesel fuel, blending of cracked stocks is essential with straight run products. This enhances the instability problem. This problem can be reduced using various stabilization procedures. In the present paper blends of cracked stocks light cycle oil (LCO) with straight run gas oil (SRGO) were stabilized by methanol extraction and hydrostabilization techniques. The insoluble from these fuels as such and their blends were stabilized and characterized using FTIR spectroscopy.     

The Effect of Weathering on the Rheology of an Atypical Waxy Crude Oil

Abstract

The Stoney Creek field, located outside Moncton, New Brunswick, Canada, has been challenged by production problems throughout its history. The oil is identified as paraffinic oil with high wax content (estimates between 19.5% to over 50% wax) but no wax deposits have been found throughout the life of the field. The pour points and viscosities were found to vary greatly with weathering and thermal history, so previous rheological information may not be accurate. The effect of weathering on the rheology of the oil was studied and results presented.     

流变学及粘度检测技术新发展

文章简述了流变学原理及其三个学派（实效学派、理论学派和学院学派）和观点和方法，概述了流体了主要是非牛顿流体的粘度特性以及影响流体流变特性的诸因素。介绍了８０年代的粘度测量技术和先进的流变分析方法和粘度测量技术。     

稠油油田边部油井井筒乳化降黏技术研究及应用

渤海某油田边部3口油井投产后产油量低,未达到预测水平。通过与同区块油井对比分析,研究出原因是油井原油黏度高,增加了井筒举升过程中的阻力,影响了电泵效率。优选成本低、降黏率高的井筒乳化降粘的技术工艺,其机理为乳化降粘和润湿降阻两方面。实验表明该复合型稠油助采剂加入定量比例的情况下,可形成黏度在10~100m P·s范围内的乳化体系;并且在温度30~60℃范围内,黏度水平稳定,降粘效果明显。3口油井实施后日均增油26m3,降粘增油效果显著。     

Physical Properties of Petroleum Waxes. I. Effect of Oil Content

Abstract

The effect of oil content on the physical properties of five microcrystalline waxes having widely different oil content have been investigated. It has been observed that the physical properties are affected to a great extent by the variation in oil content. Oil content has a profound effect on viscosity, hardness, and crystallinity of waxes. The effect is not so profound in the case of melting point.     

Physical Properties of Petroleum Waxes. I. Effect of Oil Content

The effect of oil content on the physical properties of five microcrystalline waxes having widely different oil content have been investigated. It has been observed that the physical properties are affected to a great extent by the variation in oil content. Oil content has a profound effect on viscosity, hardness, and crystallinity of waxes. The effect is not so profound in the case of melting point.     

Practical Applications of a Process Simulator of Middle Distillates Hydrodesulfurization

Abstract

An analysis of the diesel hydrodesulfurization process using a developed reactor model is presented. The reactor model within process simulator architecture was applied to different industrial process schemes. The analysis in this work uses a commercial simulator (Aspen), to conform the process scheme with a user model for the reactor unit. This user model consists of a rigorous diesel hydrodesulfurization reactor model. To couple the user model with Aspen, the kinetic and the reaction network must be available and based on model compounds. The user model employs two model compounds for the hydrodesulfurization reactions. These represent the sulfur families (dibenzothiophene and 4,6-dimethyl-dibenzothiophene). The species take the reactivity range of the sulfur compounds found in the middle distillate fractions of the Mexican crudes. One and two rings aromatic compounds are represented by the cyclohexylbenzene and methylcyclohexyltoluene, the naphthenes by the dicyclohexane and the paraffins by the n-hexadecane. Results obtained are shown by using this model in three industrial plants. The results were used to analyze the critical variables of the process showing good agreement with industrial data. The use and application of the model show the advantages of this tool to analyze actual processes, to test new configurations and the effect on the product quality when different loads with different characteristics or different processability conditions are used.     

Practical Applications of a Process Simulator of Middle Distillates Hydrodesulfurization

An analysis of the diesel hydrodesulfurization process using a developed reactor model is presented. The reactor model within process simulator architecture was applied to different industrial process schemes. The analysis in this work uses a commercial simulator (Aspen), to conform the process scheme with a user model for the reactor unit. This user model consists of a rigorous diesel hydrodesulfurization reactor model. To couple the user model with Aspen, the kinetic and the reaction network must be available and based on model compounds. The user model employs two model compounds for the hydrodesulfurization reactions. These represent the sulfur families (dibenzothiophene and 4,6-dimethyl-dibenzothiophene). The species take the reactivity range of the sulfur compounds found in the middle distillate fractions of the Mexican crudes. One and two rings aromatic compounds are represented by the cyclohexylbenzene and methylcyclohexyltoluene, the naphthenes by the dicyclohexane and the paraffins by the n-hexadecane. Results obtained are shown by using this model in three industrial plants. The results were used to analyze the critical variables of the process showing good agreement with industrial data. The use and application of the model show the advantages of this tool to analyze actual processes, to test new configurations and the effect on the product quality when different loads with different characteristics or different processability conditions are used.     

MECHANISMS OF SYNFUEL DEGRADATION. I. EFFECTS OF ORGANIC NITROGEN COMPOUNDS ON THE STABILITY OF A SHALE DERIVED DIESEL FUEL

ABSTRACT

A reliable accelerated fuel stability teat regimen has been developed and applied to the study of the storage stability of a shale derived diesel fuel marine (DFM). The results of a survey of nitrogen compounds as dopants in a stable shale DFM base fuel indicate that 3ome pyrroles and indoles may play significant roles in storage stability. A complete stability test matrix has been developed for the temperatures of 43, 65 and 80°C, for time periods between A and 179 days, and for a ten-fold concentration range of a model dopant, 2,5-dimethylpyrrole (DMP). Stability was defined by the amount of total insoluble material (filterable sediment and adherent gum) produced after stress, and also by the amount of titratable peroxide present in the filtrates of stressed fuel samples. A very regular pattern for insolubles formation was found within the test matrix. Deposit formation rates exhibited a first-order dependence on DMP concentration, with an apparent activation energy of 11-12 kcal/mol. The sediment was found to contain 12% nitrogen and 18-20% oxygen irrespective of the stress conditions employed.     

Comparative Studies on Synthetic and Naturally Extracted Surfactant for Improving Rheology of Heavy Crude Oil

Effect of surfactants on rheological properties of heavy crude oil obtained from Mehsana Asset, Gujarat, India, were studied. Studies on effectiveness towards flow behavior were made using a surfactant extracted from a tropical Indian plant Madhuca longifolia (Mahua) and nonionic surfactant Brij-30 considering various contributing parameters such as temperature, concentration, and shear rate. Tests were performed at controlled shear rate. At 25°C, 2000 ppm Mahua and Brij-30 addition reduced viscosity of crude oil by 48% and 52%, respectively. Complex and viscous modulus of crude oil decreased significantly due to addition of both the surfactants. FTIR studies of crude-surfactant mixture showed remarkable decrease in concentration of viscosity enhancing groups such as alkanes, alcoholic, and acidic groups indicating the effectiveness of both the surfactants. Naturally extracted surfactant may be used as flow improver for transporting heavy crude oil.     

KBS系列微生物采油技术研究与应用

该文介绍了新疆石油管理局克拉玛依石化厂炼油化工研究院自行研制、开发的ＫＢＳ系列微生物菌种筛选过程及使用性能,并对ＫＢＳ菌液现场施工效果及其适用条件进行了研究。１９９６ 年至１９９８ 年,新疆油田用ＫＢＳ系列微生物共施工８６ 口井、２３３ 井次,增产原油１４３５８．３ｔ,投入产出比达到１∶５ 以上。通过三年的现场应用表明,该系列微生物在新疆油田增产效果明显,具有施工简单、投资少、见效快等特点。     

绥中36-1油田试验区脱气原油/水乳化体系流变及黏度特性室内试验研究

通过室内试验研究 ,分析、总结绥中 36 - 1油田试验区脱气原油/水乳化体系在不同含水体积分数、不同温度条件下的流变性及黏度变化 ,并与其他方法结果进行比较 ;用电潜泵井生产数据间接地验证油水乳化体系的转相点。     

水平井在具有气顶的普通稠油油藏开发中的应用--以孤东油田四区为例

目前对具有气顶的普通稠油油藏提高采收率方面的研究甚少,主要矛盾是在合理利用气顶能量的同时,最大限度地提高原油的产量但又不至于发生气窜。通过对实例的研究,采用水平井进行开发,在进行水平井参数优化的基础上,解决了该矛盾。     

深层稠油掺稀油举升方法研究

深层稠油在油藏条件下具有一定的流动能力 ,但在井筒中的流动阻力却很大 ,造成生产上的困难。该文针对深层稠油油藏的特点 ,在对稠油粘温关系和深井举升工艺进行研究的基础上 ,结合实验室掺稀油降粘效果研究结果 ,对空心杆泵上和泵下掺稀油举升工艺的可行性进行了研究。设计结果及现场生产分析结果表明 ,空心杆掺稀油是一种适合于深层稠油冷采的举升方式。     

原油粘度及其对潜油电泵性能的影响

在参考国内外有关资料的基础上,根据大量的现场生产数据,就原油粘度及其对潜油电泵性能的影响进行了分析;确定了适于油田潜油电泵井实际应用的原油粘度及电泵参数修正计算方法,并编制了相应的软件,计算符合率达９０％。该方法有助于潜油电泵井运行工况的分析,可为合理选井选泵提供依据。目前已在胜利、新疆、辽河及中原等油田推广应用