The Comparison of Bitumens from Oil Sands with Different Recovery Profiles

Abstract

It has been proposed that, regardless of origin, the recovery of bitumen from oil sands is related to its viscosity. Asphaltene and resin contents are known to affect the viscosity of bitumen. In this article we compare the composition of solvent-extracted bitumens from several Athabasca oil sands with very different recovery profiles. After careful removal of any associated mineral matter by ultra-centrifugation, each bitumen sample was separated into saturate, aromatic, resin, and asphaltene (SARA) fractions by an enhanced SARA technique. The individual components were then characterized by several complementary analytical techniques, including carbon, nitrogen, nitrogen, sulfur, size exclusion chromatography molecular weight (MW_n) plus proton and ¹³C nuclear magnetic resonance spectroscopy. Based on this comparison, we see no correlation between the recovery of bitumen and its composition.     

胜利原油活性组分对原油-甜菜碱溶液体系油-水界面张力的影响

采用传统的柱色谱四组分分离方法（SARA）将胜利孤岛原油分离得到沥青质、饱和分、芳香分和胶质,采用碱醇液法萃取原油得到酸性组分。测定了正构烷烃、煤油以及原油活性组分模拟油与2种不同疏水结构的甜菜碱溶液组成的体系的油 水界面张力。结果表明,在原油活性组分模拟油 甜菜碱溶液体系中,直链甜菜碱由于疏水基团较小,与原油活性组分尤其是酸性组分和胶质发生正协同效应的混合吸附,使油 水界面上表面活性剂分子的含量增加,界面膜的排布更紧密,导致油 水界面张力降低;支链甜菜碱由于具有较大尺寸的疏水基团,煤油中少量的活性物质即可将油 水界面张力降至超低(<10-3 mN/m),而原油活性组分的加入,则使界面上表面活性剂分子的排布被破坏,削弱了界面膜原有的紧密性,导致油 水界面张力大幅度升高。     

胜利原油活性组分对其与烷基苯磺酸盐溶液组成的体系油-水界面张力的影响

 采用柱色谱四组分分离方法(SARA)对胜利原油进行分离,依次得到沥青质、饱和分、芳香分和胶质;采用碱醇液法萃取胜利原油得到其酸性组分,测定了各原油活性组分模拟油与烷基苯磺酸盐配制的系列标准溶液组成体系的油-水界面张力。结果表明,原油的酸性组分在低质量分数时通过改变油相的等效烷烃碳数（EACN）影响体系的油-水界面张力;高质量分数时则与表面活性剂混合吸附,使得体系油-水界面张力大幅度升高。胶质对其模拟油-表面活性剂标准溶液体系的油-水界面张力的影响与酸性组分的规律一致;沥青质的界面活性弱于酸性组分,混合吸附能力较弱,高质量分数时使体系油-水界面张力小幅度升高;饱和分和芳香分只影响油相的性质。     

A Study on the Effect of Hydrogenated Residual Oil Four-Component Properties on Sulfur Distribution of Light Oil in the FCC Process

Abstract

Based on the data of a hydrogenated residual oil fluid catalytic cracking (FCC) process in a petrochemical company, the effect of hydrogenated residual oil four-component (saturates, aromatics, resins, and asphaltenes; SARA) property on sulfur distribution of light oil in an FCC process was reviewed and a conjunction formula between sulfur distribution of light oil and SARA property was established. The associated results indicated that sulfur distribution of light oil in the FCC process was reduced as the saturate, aromatic, and resin component of hydrogenated residual oil increased, and the effect factor decreased in the order, saturate > aromatic > resin. On the other hand, the enhancement of the asphaltene component made the sulfur distribution of light oil increase slightly. In addition, the conjunction formula was used to predict sulfur distribution of light oil by the other hydrogenated residual oil feedstock and the calculated sulfur distribution of light oil was in good agreement with the actual data; all the predicted relative errors were less than 5% and the mean relative error was 2.98%. The results showed that the established conjunction formula possessed good predictive features and reliability.     

CHARACTERIZATION OF HEAVY RESIDUA BY AAPPLICATION OF A MODIFIED D 2007 SEPARATION AND ELECTRON PARAMAGNETIC RESONANCE

ABSTRACT

Seven atmospheric residua (343^°C + [ 65O^°F + ]) were separated into saturate, aromatic, resin, and asphaltene fractions for detailled assessment of feed structure. The weight percent distribution of the fractions revealed two groupings of the residua. One grouping exhibited 20 wt % saturate composition, while the other only 10 wt %. The residua also exhibited high polar content (resin and asphaltene fractions) consisting of over 40% of the total residua. These results are related to the sulfur composition of the residua, and Indicate a fundamental relationship between the aromatic content and sulfur content. Discussion of the accuracy of the separation technique Is also Included.

The vanadium binding sites In the separated fractions were investigated by EPR spectroscopy. The resin and asphaltene fractions all appear to be dominated by 4N and N 0 2S coordination spheres. Discussion of this technique is also included.     

The low temperature oxidation characteristics of SARA fractions in air flooding process

The Low Temperature Oxidation (LTO) characteristics of SARA fractions isolated from light crude oil were studied applying the static oxidation experiments. The results show that the LTO reaction of SARA fractions can occur when temperature is above 50°. Under reservoir conditions, the oxidation activities of the SARA fractions were resin > aromatics > saturate. The theoretical LTO reaction rate of crude oil calculated based on the SARA oxidation characteristics is in good agreement with the measured value. Therefore, it is an effective method to reveal the LTO mechanism of crude oil by studying the LTO mechanism of SARA fractions.     

TLC/FID分析原油SARA组成方法研究

以渤海原油为研究对象,建立原油棒状薄层色谱／氢火焰离子化检测器（TLC／FID）族组分分析方法,对原油的四个族组分（饱和烃、芳烃、胶质、沥青,SARA）进行了分析。并对其影响因素展开次数、点样量、展开剂的干燥方式进行了优化,在优化所得条件下,方法的精密度RSD值为3．54％,方法重现性RSD值为3．23％。与文献报道方法相比,本文建立的方法,可将原油中的胶质和沥青两个组分分开,更能全面反应原油的族组成成分,具有分析速度快、有机溶剂用量少、操作简单等特点。最后将建立的方法应用到不同来源的原油中,结果令人满意。     

反应时间对加氢残渣油四组分含量和结构的影响

以沙特轻质原油减压渣油（ALVR）为原料,采用高压釜考察了不同反应时间下加氢反应后残渣油的四组分含量及其结构组成变化。结果表明,与未加氢渣油相比,加氢残渣油中的饱和分含量大幅度增加,而芳香分、胶质和沥青质的含量均降低,四组分的H/C原子比和平均相对分子质量均降低,芳碳分率升高。加氢残渣油的四组分含量随反应时间的增加均呈规律性变化。随着加氢反应时间的增加,四组分的H/C原子比和平均相对分子质量降低,芳香分、胶质和沥青质的芳碳分率增加,胶质和沥青质的总环数和芳环数均降低。渣油加氢反应过程中,其四组分均发生了明显的氢解和脱烷基反应,胶质和沥青质结构单元间的各种桥键可发生明显的断裂,导致其结构单元数减少。不同来源和属性的渣油加氢反应后各组分的结构变化有一定区别。     

超声波处理对渣油加氢反应过程胶体性能的影响

超声波处理改变了渣油饱和分、芳香分、胶质、沥青质(SARA)的含量、结构和分布状态,使渣油胶体稳定性得到改善。沥青质的含量、结构和分布状态对渣油胶体稳定性有重要影响。超声波处理改变了沥青质的结构,减少了渣油中沥青质的含量,大幅增加了溶胶能力强的胶质的含量,改善了沥青质的分散状态,使渣油胶体稳定性增加。超声波处理后渣油四组分理化性质的变化改善了渣油品质,提高了渣油和沥青质的反应性能,加氢反应深度增加,产物分布改善,但加氢残渣油的胶体稳定性降低。超声波处理对渣油及其加氢残渣油的胶体稳定性具有重要影响。     

The Chemical Composition of Solubility Classes from Athabasca Bitumen Pitch Fractions

Abstract

As the Canadian supply of light crudes diminishes, refineries have necessarily been required to deal with more difficult to process oilsands bitumen and heavy oils. Nearly 50% of bitumen consists of a residuum that cannot be easily upgraded. A better understanding of the chemistry of this material is the key to achieving overall optimal yields of commercially useful products. In recent years, the application of supercritical fluid extraction (SCFE) with pentane has been successful in separating the bitumen residuum into a number of narrow fractions based on solubility parameters and molecular weight. In combination with advanced characterization techniques this approach has proved to be useful in elucidating the complexity of bitumen chemistry. To provide further insights into the chemistry of bitumen pitch we now extend this established approach to the solubility classes (saturate, aromatics and resins) derived from the bitumen fractions, or front-cuts, separated during the SCFE process with pentane. The amount of the saturate class present in the front-cuts decreases rapidly with cumulative yield. In the same range, resin content increases continuously while aromatic content passes through a maximum. No asphaltene is present in the front-cuts; this component is separated in the pentane insoluble end-cut fraction during SCFE. Both aromatics and resins from the front-cuts show a trend for increasing aromatic content and decrease in H/C atomic ratios at higher cumulative yields. This is a reflection of increasing number of aromatic rings, with a higher degree of condensation and decreasing degree of substitution, for larger and more complex molecules. In terms of structural parameters and molecular sizes we find relatively minor differences between the corresponding aromatic and resin fractions in each front-cut. The most noteworthy difference between these SARA classes lies in the significantly higher nitrogen contents of the resin class.     

ASPHALTENE AND RESID PYROLYSIS: EFFECT OF REACTION ENVIRONMENT

ABSTRACT

Hondo and Maya vacuum resids and their isolated asphaltenes were pyrolyzed at 400, 425, and 450^°C (752, 797, 842^°F) for batch holding limes ranging from 20 to 180 minutes. Maltene, asphaltene, and coke product fractions were isolated by a solvent extraction sequence; gas yield was determined gravimetrically. Results were summarized in terms of a lumped reaction network. The variation of product yields, kinetics, and apparent activation energies with feedstock and asphaltene environment provided insight into asphaltene structure and thermal reaction pathways.     

减压渣油微观相结构特性的分子模拟

选用4种模型化合物代表减压渣油四组分(SARA),采用分子动力学模拟了减压渣油微观相结构,发现不同结构分子间相互作用的差异是减压渣油微观非均匀分布的本质原因,并通过电子分布特性分析了不同结构分子间相互作用差异的本质原因。沥青质分子间强相互作用使得沥青质分子自缔合形成聚集体;而多个胶质分子与沥青质分子的强相互作用封闭了沥青质分子自身进一步发生相互作用的活性位;同时,与胶质分子、饱和烃分子具有强相互作用的芳香烃分子将沥青质 胶质分子形成的聚集体分散在由芳香烃 饱和烃分子构成的连续相内,其中芳香烃分子更靠近胶质分子。因此,增加沥青质、饱和烃分子的含量会促进沥青质聚集,降低减压渣油稳定性;增加胶质、芳香烃分子的含量会阻碍沥青质聚集,提高减压渣油稳定性。     

原油及渣油中Fe含量分布及其存在形态

测定了委内瑞拉、克拉玛依、辽河和大港4种原油及其常压渣油(AR)、减压渣油(VR)中的Fe含量,并分析了原油及其AR、VR的四组分中的Fe含量分布和原油及其AR、VR中Fe的存在形态及分布。结果表明,从原油、AR到 VR,随着油样沸程的升高,其Fe含量不断增加,并且主要富集在VR中;Fe主要分布于胶质、沥青质组分中,并且随着原油馏分沸程的升高,沥青质中的Fe含量分布不断增加;原油及渣油中的Fe主要是油溶性Fe,占总Fe质量分数的75%～99%,且同一种原油中油溶性Fe的含量随着该原油馏分沸程的升高而增加,原油及其AR、VR中石油酸Fe的含量与原油的酸值大小有关,卟啉Fe和非卟啉Fe含量之和随着原油的重质化而增加。     

南海原油胶质、沥青质结构表征及原油降黏研究

南海原油储量丰富,其开发利用具有重要的经济价值和战略意义。从南海原油中分离出胶质和正庚烷沥青质并对其进行表征,合成了含氮长链聚合物型降黏剂,同时考察了合成降黏剂对南海原油的降黏效果。结果表明：南海原油属高胶质、高沥青质原油,胶质和沥青质容易形成缔合结构是其黏度较高的主要原因;胶质和沥青质分子具有由烷基链连接起来的含有侧链的芳香片结构,且含有形成氢键的极性基团,胶质和沥青质的平均相对分子质量分别为760和1 129;构建的南海原油胶质和沥青质平均分子结构式参数与表征结果吻合;添加1 000 μg/g降黏剂的南海原油在15 ℃和40 ℃下的降黏率分别为44.2%和40.2%,屈服应力值从1 070 Pa降至563 Pa,降黏效果显著。     

Soil Microbial Degradation of Vacuum Residue

Abstract

The effect of microbial consortia on the alteration of petroleum residual structure and portions was studied, which can propose an alternative or complementary method for stringent upgrading heavy crude oil methods, which consist of heavy and complex hydrocarbons. Biological processing of petroleum heavy fractions and residua may provide an alternative or complementary process in refining heavy crudes—the dominant refinery feed in the future—with less severe process conditions and higher selectivity to upgrade heavy fractions of crude oil. The primary objective was to observe the ability of an indigenous bacterial consortium taken from a soil bellow the vacuum column contaminated with vacuum residue (VR) for several decades from the Tehran refinery distillation unit, in degradation of residua components. Enrichment with VR, as sole source of carbon and energy, is the selected biosurfactant-producing microbial consortium. The biodegradation of net VR using indigenous consortia from this specific ecosystem was studied. The considered period of biodegradation of these heavy hydrocarbons was remarkably shorter than usual studies. Bacterial growth and VR biodegradation ability of this consortium analyzed with SARA test in 20 days. Studying the inoculum size and aeration effect revealed the significance of oxygen for this consortia activity and the similarity of 7% and 5% inoculation on alteration percentage of alkane, aromatic, and asphaltene and resin in VR. Results study revealed a 30.4%, 6.9%, and 9.4% decrease in the asphaltene, aromatics, and saturated aliphatic contents of VR, respectively, in only 20 days in 30°C at 150 rpm.     

A Study of the Characteristics in Blended Crudes at the Optimal Activation State: Part I

Abstract

With the increasing need for crude oil and the improving processing capacity, refining of crude blending has become increasingly popular. This article studied the effect of blending refining at the various ratios by the dynamic equilibrium flash vaporization equipment. Nuclear magnetic resonance (NMR) and groups of oil analysis (SARA) were also applied to estimate the blended crudes at the optimal activation state at which the blending crude oils had the maximum distillation yield. The NMR of three groups of blended crudes have elucidated that the resin content at the optimal blended percentage is close to or lower than the theoretical value. And the resin content is obviously higher than theoretical value at the worst blending ratio. The asphaltene content increased, the residua became denser, and branching index decreased at the optimal blended percentage.     

Evaluation of Trace Metals and Physical Properties of Nigerian Crude Oil Saturate Fraction

Analyses of trace elements and physical properties of the saturate fraction of Nigerian crude oil were done in order to establish the characteristics that may aid the developmental processes of the natural resources. Crude oil samples were collected from three different oil fields in Niger-Delta area of Nigeria. The saturate fractions were eluted by column chromatography using n-hexane. The saturate fractions were investigated for functional groups using Fourier transform infrared spectrometry (FT–IR); the elemental concentrations were determined using Atomic absorption spectrometry, while the physical properties (flash point, ash content, refractive index, and color) were determined using standard analytical methods. The results revealed that the infrared spectra of the saturate fraction of the Nigerian crude oil showed mainly the presence of C-H(CH₃) and C-H(CH₂) functional groups, indicating high purity of the samples. The concentrations of the analyzed elements (Mn, Cu, Co, Zn, Fe, V, Cr, and Ni) in the saturate fraction were generally low compared to other fractions of Nigerian crude oil. This study revealed that Co has the highest mean concentration of 1.81 ± 0.36 mg/L, while Mn has the lowest mean concentration of 0.04 ± 0.02 mg/L. The t test values for the comparison of the elemental concentrations of Nigerian crude oil /saturate fraction and crude oil asphaltene/saturate fraction showed significant difference (except Mn) with respect to Nigerian crude oil /saturate fraction. The cluster analysis for the elements showed two groups, which are fairly well correlated indicating similar source and similar chemical affinity. The cross-plot analysis of the Nigerian crude oil and its saturate using elemental concentrations as the variables showed a strong positive inter element correlation since (R² = 0.71), establishing a relationship between the Nigerian crude oil and the saturate fraction. The color of the saturate fraction ranged from off-white to colorless. The results of analysis provide useful information on its conversion mechanism and environmental implications of the development of the fossil fuel deposit.     

CHARACTERIZATION OF HEAVY RESIDUA BY APPLICATION OF A MODIFIED D 2007 AND ASPHALTENE SEPARATION: EFFECT OF SOLVENTS ON PHYSICAL AND CHEMICAL PROPERTIES OF FRACTIONS DERIVED FROM HONDO 850°F RESIDOOM

Hondo 850 ^°F residuum was separated into saturate, aromatic, resin, and asphaltene fractions by a modified D 2007 and asphaltene separation. Two different asphaltene precipitation solvents were used — isooctane and heptane — and differences in selected physical and chemical properties of the derived fractions were compared.

The principal difference in the use of the two solvents was weight recovery after the separation. Isooctane yielded good recovery, while heptane exhibited poor recovery. Isooctane precipitated substantially more asphaltenes, as predicted from the solubility parameters of the two solvents.

The metals concentrations in the fractions were comparable for each solvent — no metals in the saturate and aromatic fractions, approximately 300 and 1500 ppm Ni + V in the resin and asphaltene fractions respectively. The relative distribution was also similar for both solvents, with the highest percentage coming from the asphaltenes.     

THE MIDDLE CAMBRIAN SUCCESSION IN THE CENTRAL BALTIC BASIN: GEOCHEMISTRY OF OILS AND SANDSTONE RESERVOIR CHARACTERISTICS

Some 36 oilfields, all producing from Middle Cambrian (Deimena Group) sandstones, are located in the central Baltic Basin in an area covering onshore Lithuania and Kaliningrad (Russia) and the adjacent offshore. This paper presents new data on the composition of crude oils from fields in this area and reviews the reservoir properties of the Deimena Group sandstones. Twenty‐one crude oil samples from fields in Lithuania and Kaliningrad were analysed by standard techniques including GC and GC‐MS. The oils had densities of 790.5 to 870.0 kg/m³, and had low asphaltene (<2.2%) and sulphur (<0.44%) contents. The gasoline fraction (b.p. >200°C) ranged from 12–34%. The saturated hydrocarbon content was 35.3 to 77.8%, and the ratio of saturate to aromatic hydrocarbons was 2.1–5.2, indicating long‐distance migration or high thermal maturities. GC analyses of saturate fractions indicated a composition dominated by n‐alkanes with a maximum at C₁₃–C₁₅ and reduced abundance in the C₂₀–C₃₅ range. The analysed crude oil samples are characterized by relatively low concentrations of steranes and triterpanes. Biomarker data indicated an algal origin for the precursor organic matter and a clastic‐dominated source rock. Sterane isomerization ratios imply that the oils are in general relatively mature. Exceptions are samples from the Juzno Olempijskoye and Deiminskoye fields, Kaliningrad, which were early mature. Oil from well Gondinga‐l (Lithuania) was lightly fractionally evaporated and has a relatively higher density, higher viscosity, higher asphaltene content and lower content of saturated fractions. Stable carbon isotope ratios of crude oils and saturated and aromatic fractions were analysed. Whole oils showed little carbon isotope variation, but there were significant differences in δ¹³C ratios for saturated and aromatic fractions. The geochemical data show differences in oil sourcing and indicate the possible existence of different kitchen areas in the Kaliningrad region. Vertical and lateral variations in Deimena Group reservoir properties are controlled by variations in quartz cementation. In fields in western Lithuania, sandstone porosity ranges from 0.7 to 20% and permeability from 20 mD to 300 mD; in fields onshore Kaliningrad, porosity is up to 34% and gas permeability up to 4.8 D. Wide variations in porosity and permeability occur at a field scale.     

CHARACTERIZATION OF HEAVY RESIDUA BY AAPPLICATION OF A MODIFIED D 2007 SEPARATION AND ELECTRON PARAMAGNETIC RESONANCE

Seven atmospheric residua (343^°C + [ 65O^°F + ]) were separated into saturate, aromatic, resin, and asphaltene fractions for detailled assessment of feed structure. The weight percent distribution of the fractions revealed two groupings of the residua. One grouping exhibited 20 wt % saturate composition, while the other only 10 wt %. The residua also exhibited high polar content (resin and asphaltene fractions) consisting of over 40% of the total residua. These results are related to the sulfur composition of the residua, and Indicate a fundamental relationship between the aromatic content and sulfur content. Discussion of the accuracy of the separation technique Is also Included.

The vanadium binding sites In the separated fractions were investigated by EPR spectroscopy. The resin and asphaltene fractions all appear to be dominated by 4N and N 0 2S coordination spheres. Discussion of this technique is also included.