VISCOSITY AND SOLUBILITY OF MIXTURES OF BITUMEN AND SOLVENT

Abstract

The solubilities of three bitumen samples (Suncor, Syncrude and Lloydminster) in five solvents were examined and prediction on the various bitumen-solvent mixture viscosities were made with Cragoe equation. By calculating the Cragoe constant ‘a’ for each mixture and using the average value in the Cragoe equation the prediction accuracy of the equation was improved by over 60%. Bitumen-naphtha mixtures showed the best viscosity prediction characteristics.

The solubility of the asphaltenes in the bitumen was highest in toluene among the five solvents However, naphtha, showed a moderate solvating power, which negligibly varied over the range of composition studied. Therefore naphtha, a solvent derived from bitumen was recommended as the most appropriate solvent for reducing the viscosity bitumen.     

A CORRELATION FOR VISCOSITY AND SOLVENT MASS FRACTION OF BITUMEN-DILUENT MIXTURES

A simple equation is presented for predicting the kinematic viscosity of bitumens and heavy oils mixed with diluents. The correlation has been shown to provide accurate viscosity estimates of these mixtures for a wide range of data and requires only the knowledge of the pure bitumen and pure solvent viscosities at any given temperature.

The correlation makes use of a viscosity reduction parameter which reduces error significantly when compared to similar equations presented by Chirinos et al. (1983), and Cragoe (1933). For a total of 89 data points, excluding the pure bitumens and diluents values, the correlation yielded an overall average absolute deviation of about 14 percent. The same equation was applied to predict the mass fraction of diluent required to reduce bitumen viscosity to pumping viscosity. Predicted values matched experimental values very well, with an overall average absolute deviation of about 6 percent.     

沥青材料的动态粘度测试及流变模型

通过对沥青材料进行同轴旋转剪流变试验。测试了沥青材料的动态粘度，建立了沥青关超常温下的流变模型，并就有关问题进行了讨论。     

高分子溶液与微乳液的混合粘度：Huggins参数

本文研究了聚丙烯酰胺的分子量和水解度对聚丙烯酰胺／微乳混合液粘度的影响，利用混合高分子稀溶液的比浓粘度与浓度关系式，从Ｈｕｇｇｉｎｓ参数研究了大分子线团与微乳液滴之间的相互作用。     

PRELIMINARY PHASE DIAGRAMS FOR BITUMEN/ HEAVY OILS AND RELATED MIXTURES

The phase behaviour of heavy oil mixtures was studied using an X-ray imaging system. Batch phase experiments were performed at temperatures and pressures up to 725 K and 7 MPa. Complex phase behaviour such as liquid-liquid-vapour and solid-liquid-liquid-vapour were observed and preliminary experimental phase diagrams were constructed. This observed complex phase behaviour is consistent with thermodynamic theory and such phase behaviour can be modelled using the Peng-Robinson equation of state and the tangent plane criterion. These latter points are illustrated through the phase diagram for a model reservoir fluid (ethane + propane + n-butane + phenanthrene) which exhibits solid-liquid-liquid-vapour phase behaviour. Example predicted and experimental phase diagrams are presented for this model system.     

PRELIMINARY PHASE DIAGRAMS FOR BITUMEN/ HEAVY OILS AND RELATED MIXTURES

ABSTRACT

The phase behaviour of heavy oil mixtures was studied using an X-ray imaging system. Batch phase experiments were performed at temperatures and pressures up to 725 K and 7 MPa. Complex phase behaviour such as liquid-liquid-vapour and solid-liquid-liquid-vapour were observed and preliminary experimental phase diagrams were constructed. This observed complex phase behaviour is consistent with thermodynamic theory and such phase behaviour can be modelled using the Peng-Robinson equation of state and the tangent plane criterion. These latter points are illustrated through the phase diagram for a model reservoir fluid (ethane + propane + n-butane + phenanthrene) which exhibits solid-liquid-liquid-vapour phase behaviour. Example predicted and experimental phase diagrams are presented for this model system.     

沥青粘滞性对混合料蠕变特性的影响

从解决沥青路面的车辙、拥包等问题出发，研究了沥青混合料的蠕变特性、沥青结合料的剪切蠕变，以及沥青混合料的劲度模量与沥青粘度的关系。研究结果认为，现行的马歇尔试验方法不足以评价沥青混合料的热稳定性；蠕变试验能充分反映沥青混合料的粘流性质，说明沥青路面产生车辙的机理；沥青结合料的粘度对混合料的抗永久变形能力有直接影响，因此抗车辙沥青结合料必须具备足够的粘度。     

VISCOSITY ESTIMATION FOR BITUMEN-DILUENT MIXTURES

A generalized viscosity correlation has been used to predict the viscosity-temperature relationship of bitumen mixed with various proportions of diluents such as GCOS synthetic crude, mobil solvent and naphtha. The results showed that the correlation can accurately predict the viscosities of bitumen-diluent mixtures based on a single viscosity measurement at 30°C and one atmosphere. For 300 experimental points, the correlation yielded an overall average absolute deviation between predicted and experimental values of 8.7%. It is found that the correlation gave high percent errors for mixtures with high disparity in viscosity between bitumen and diluent.     

非石油基油品对渣油掺稀降黏效果及掺稀模型研究

采用水上油、页岩油和煤柴油等3种非石油基稀油对渣油进行掺稀降黏,考察了温度、稀油类型和掺稀比(稀油与调合油的质量比)对调合油黏温关系的影响,并基于实验数据,将由氩模型微分方程导出的液体黏度理论方程拓展应用到渣油掺稀调合油的黏温关系描述中,建立渣油掺稀黏度模型。结果表明:3种非石油基稀油均能够用于对渣油进行掺稀降黏,掺稀比越高,调合油黏度降低幅度越大,在掺稀比低于0.3的条件下,页岩油和水上油降黏效果较好;稀油对渣油沥青质基本片层结构的缔合作用力的影响是造成调合油黏度降低的重要原因;所建模型的计算值与实验值吻合较好,模型参数反映了调合油的分子构成,能较好地描述渣油掺稀降黏的黏温关系。     

VISCOSITY PREDICTION OF HYDROCARBON MIXTURES BASED ON THE FRICTION THEORY

The application and capability of the friction theory (f-theory) for viscosity predictions of hydrocarbon fluids is further illustrated by predicting the viscosity of binary and ternary liquid mixtures composed of n-alkanes ranging from n-pentane to n-decane for wide ranges of temperature and from low to high pressures. In the f-theory viscosity predictions the SRK and the PRSV EOS have respectively been used. Further, a comparison with the widely used LBC viscosity model shows that better results are obtained with the f-theory models. The obtained AAD% is within or close to the experimental uncertainty, which is satisfactorily for most applications related to the oil industry.     

VISCOSITY PREDICTION OF HYDROCARBON MIXTURES BASED ON THE FRICTION THEORY

The application and capability of the friction theory (f-theory) for viscosity predictions of hydrocarbon fluids is further illustrated by predicting the viscosity of binary and ternary liquid mixtures composed of n-alkanes ranging from n-pentane to n-decane for wide ranges of temperature and from low to high pressures. In the f-theory viscosity predictions the SRK and the PRSV EOS have respectively been used. Further, a comparison with the widely used LBC viscosity model shows that better results are obtained with the f-theory models. The obtained AAD% is within or close to the experimental uncertainty, which is satisfactorily for most applications related to the oil industry.     

高黏度减五线馏分油NMP精制中试研究

以大庆、沈北混合高黏度减五线馏分油为原料,在小型试验的基础上,进行了4组不同条件下的NMP精制中型试验。结果表明：中型操作条件下的精制油在脱蜡后,其质量均满足500SN的产品质量要求;在无水和含水为2.0%,剂油体积比为0.75和1.38条件下精制深度可以满足HVIS中500SN的要求;在含水为1.5%,剂油体积比1.40条件下精制深度可以满足HVIW中500SN的要求;在含水为2.5%,剂油体积比为1.51条件下产品质量除氧化安定性不能满足要求外,其它质量指标均能满足HVIW中500SN的要求。随着溶剂中水含量的增加,需增大剂油比来满足精制深度要求。     

VISCOSITY PREDICTION OF CARBON DIOXIDE HYDROCARBON MIXTURES USING THE FRICTION THEORY

The general one-parameter f-theory model has been used in conjunction with the SRK and the PR EOS to predict the viscosity of well-defined carbon dioxide + hydrocarbon mixtures. The predicted viscosities are within the uncertainty appropriate for most industrial applications. Although the studied mixtures are simple representations of real oil mixtures with carbon dioxide, the f-theory approach can easily be extended to more complex scenarios, such as the simulation of carbon dioxide enhance oil recovery. Additionally, a comparison with the LBC model, which is a widely used model in the oil industry, has been carried out. In contrast to the f-theory models, the strong dependency that the LBC model has on the accuracy of the density is clearly evident for the kind of mixtures studied in this work. Furthermore, it is shown how the phase behavior complexity that carbon dioxide + hydrocarbon mixtures develop may have a direct influence on the performance of the viscosity modeling and prediction.     

甲烷和乙烷在风城稠油中的溶解度及气体饱 和稠油的粘度和密度

用实验室建立的正反循环式气液平衡仪,在６５ ．０ —１８ ．０ ℃、常压至１０ Ｍ Ｐａ 压力范围内,测定了甲烷、乙烷及摩尔比１∶１ 的甲烷乙烷混合气在新疆风城超粘稠油中的溶解度、平衡体系的气液相组成、气体饱和稠油的粘度和密度数据。讨论了溶解度、粘度和密度与温度、压力和气体性质的关系。     

甲烷和乙烷在风城稠油中的溶解度及气体饱和稠油的粘度和密度

用实验室建立的正反循环式气液平衡仪,在６５．０－１８．０℃,常压至１０ＭＰａ压力范围内,测定了甲烷、乙烷及摩尔比１：１的甲烷乙烷混合气在新疆风城超粘稠油中的溶解度、平衡体系的气液相组成,气体饱和稠油的粘度和密度数据。讨论了溶解度、粘度和密度与温度、压力和气体性质的关系。     

快速溶剂萃取法提取印尼油砂沥青的工艺研究

采用快速溶剂萃取技术提取油砂沥青,通过单因素试验和正交试验得出加压溶剂萃取技术的最佳工艺参数。研究结果表明,在高压条件下,混合适量硅藻土分散剂,快速溶剂萃取法提取油砂沥青比传统索氏抽提与费舍尔试验更有优势。利用正交试验获得快速溶剂萃取法提取油砂沥青的最佳工艺参数为：压力10 MPa,土砂比(硅藻土与油砂的体积比)2∶1,萃取温度160℃,循环次数5次,溶剂选择四氢呋喃,单次静态萃取时间12 min。     

VISCOSITY PREDICTION OF CARBON DIOXIDE + HYDROCARBON MIXTURES USING THE FRICTION THEORY

ABSTRACT

The general one-parameter f-theory model has been used in conjunction with the SRK and the PR EOS to predict the viscosity of well-defined carbon dioxide + hydrocarbon mixtures. The predicted viscosities are within the uncertainty appropriate for most industrial applications. Although the studied mixtures are simple representations of real oil mixtures with carbon dioxide, the f-theory approach can easily be extended to more complex scenarios, such as the simulation of carbon dioxide enhance oil recovery. Additionally, a comparison with the LBC model, which is a widely used model in the oil industry, has been carried out. In contrast to the f-theory models, the strong dependency that the LBC model has on the accuracy of the density is clearly evident for the kind of mixtures studied in this work. Furthermore, it is shown how the phase behavior complexity that carbon dioxide + hydrocarbon mixtures develop may have a direct influence on the performance of the viscosity modeling and prediction.     

印尼油砂溶剂抽提工艺条件的研究

对印尼油砂的组分、结构和粒径特征进行分析。分析结果表明，从印尼油砂中分离稠油沥青适用的方法是溶剂抽提工艺。考察了三氯乙烯、甲苯、石油醚、石脑油、含极性组分的石脑油5种溶剂对抽提效果的影响，确定较佳的抽提溶剂为含极性组分的石脑油。考察了印尼油砂溶剂抽提的工艺条件，推荐的最佳工艺参数为：溶剂与油砂的体积比1.3：1，抽提温度50～60 ℃，抽提时间15～30 min，搅拌速率100～300 r/min。在该条件下，稠油沥青一级抽提率达85%，二级抽提率达93%。     

DISTRIBUTION AND TYPES OF SOLIDS ASSOCIATED WITH BITUMEN

In the conventional Hot Water Extraction Process bitumen is separated as a froth that is then diluted with naphtha and subjected to two stages of centrifugation. The resulting bitumen solution still contains residual water, dissolved salts and mineral solids. Before upgrading the solvent and other volatile components are removed by topping at 524°C. The salts and mineral solids remain with topped bitumen; their presence can lead to serious operational problems in the bitumen upgrading process. In the present work the solids associated with bitumen (BS) have been identified as mainly ultra-fine (nano sized) aluminosilicate clays coated with strongly bound toluene insoluble organic material having “asphaitene characteristics”. It is proposed that these ultra-fine clays with their strong tendency to collect at oil-water interfaces, are the key component responsible for the presence of intractable water and associated salts in bitumen froth.     

烃类溶剂的生产应用及发展前景

介绍了近期国内外烃类溶剂的种类及其应用情况 ,对我国烃类溶剂的发展提出了建议。