渣油的特征化参数

在对国外5种减压渣油进行超临界流体萃取分馏及其窄馏分性质分析的基础上，考察了已有的渣油特征化参数KH对国外减压渣油的适用性，研究结果表明，已有的渣油特征化参数KH和国外减压渣油的化学组成偏差较大，因此，笔者建立了一个新的渣油特征化参数KR，可以比较准确地关联国内外11种渣油馏分的性质和组成，并表征渣油馏分的催化裂化及热反应性能。     

会议消息

“渣油超临界溶剂脱沥青技术开发”通过国家级鉴定由石油大学(华东)、中国石油化工总公司北京设计院和抚顺石化公司石油二厂承担的“渣油超临界溶剂脱沥青技术开发”于1990年12月4～5日在北京通过了国家级技术鉴定。该项目的主要内容包括:1.渣油-超临界溶剂的相行为观察与相平衡的研究(实验室),建立了渣油超临界溶剂脱沥青的热力学数学模型。2.在小型连续超临界溶剂脱沥青装置上,进行了大庆减压渣油、孤岛减压渣油和常压渣油、单家寺减压渣油和常压渣油等的超临界溶剂脱沥青的工艺条件和产品性质的研究。     

减压渣油特征化参数的研究

在对多种渣油进行超临界流体萃取分馏及窄馏分性质分析的基础上，计算了三种减压渣油超临界流体萃取分馏窄馏分的Ｗａｔｓｏｎ Ｋ值，发现适用于原油及其轻馏分的ａｔｓｏｎＫ值不能表达渣油及其馏分的特性和分类。首次提出了以Ｈ／Ｃ原子比、分子量及密度三因素来表征减压渣油的特征参数ＫＨ。利用文献数据，以ＫＨ为依据对渣油的物性、热裂化、催化裂化及高温热解的结果进行了分析研究，表明ＫＨ值可以较好地体现渣油或其馏分的整     

渣油超临界萃取馏分溶解度参数的测定新方法

采用RUSKA2370-601型高压无汞双釜PVT装置，测定了加拿大Athasca bitumen减压渣油（VTB）的超临界萃取馏分在丙烷中的液-液相平衡，用Scatchard-Hildebrand正规溶液理论公式计算了渣油馏分的溶解度参数，还考察了丙烷与渣油馏分的质量比（ms/mo=1.0-5.5)、实验温度（32-50℃）和压力（4-6MPa)对渣油馏分溶解度参数的影响。结果表明，渣油馏分的溶解度参数随丙烷与渣油馏分的质量比及压力变化有极大值，随温度知高而降低，且与丙烷的溶解度参数之差增大，互溶性变差。     

沈阳原油减压渣油合理利用的探讨

沈阳原油减压渣油富含微晶蜡而胶质、沥青质含量较少，可通过溶剂脱沥青和溶剂脱油工艺生产高滴点微晶蜡等产品。文中给出了沈阳渣油的３种脱沥青的试验结果，据此提出了合理利用沈阳渣油的建议，并对比了沈阳渣油脱沥青生产微晶蜡与延迟焦化生产轻质油和石油焦的经济性，说明了前者的优越性。建议开展沈阳渣油超临界丙烷精密分离的开发工作。     

减压渣油与超临界亚组分的元素组成及SARA分析

用正戊烷为溶剂，在超临界条件下将６种国内与２种国外减压渣油分离成不同的宽馏分和窄馏分，测试了它们的残炭值，ＳＡＲＡ及元素组成。结果表明，渣油的残炭值与氢碳比密切相关；各种渣油的元素和化学组成的含量及分布是有差别的；镍倾向于分布在重组分中，孤岛和辽河渣油最为明显；大庆，华北渣油为低硫，高氮原油，氮和硫在渣中中分布平均；     

超声波处理对减压渣油分子结构的影响

为提高渣油的质量,对渣油进行了超声波处理,其输出功率为800W,温度为70°C,间隔为0到11分钟。实验表明,超声波处理7min后,黏度和残炭率分别降低14.1%和7.4%。饱和分含量增加,芳烃、胶质和沥青质含量下降。用FT-IR、1H-NMR等手段对平均分子结构参数进行了表征,而超声处理时间长达7分钟,渣油参数的变化也越来越大。超声波处理产生的机械搅拌和空化作用引起减压渣油分子的一系列变化。微观变化影响了平均分子结构的参数,这通常在SARA分数中显示出来。采用热重法分析了超声波处理后减压渣油热反应特性的变化。随着超声波处理时间的增加,热解所需的表观活化能逐渐降低,温度也随之降低。     

单家寺稠油超临界抽提改质

以天然气凝析油的戊烷馏分为溶剂,研究了单家寺稠油全馏分、常压渣油和减压渣油的超临界抽提改质。考察了抽提温度、压力和溶剂比等工艺条件对抽提过程的影响;不同抽提深度的脱沥青油(DAO)和沥青的性质;原油、常压渣油和减压渣油在抽提方面的差别。根据工艺条件的研究和实验设备流程提出了超临界逆流接触抽提的工业流程。     

减压渣油结构参数及氢含量的预测

利用减压渣油及其超临界流体萃取分馏馏分的基本性质数据,由多元线性回归分析法得到了结构参数的关联式。并给出了在缺乏元素分析的条件下,渣油氢含量的预测式。模型简便可靠,有较大的实用价值。     

减压渣油胶体稳定性的分子模拟

分子结构特性决定分子间相互作用,进而决定其溶解性能。通过分子模拟研究减压渣油不同结构分子的分子间相互作用、互溶性及由此导致的渣油胶体稳定性。研究表明,芳环数目越多、烷基侧链越短的分子结构内聚能密度越大,溶解度参数越大。在渣油体系中,沥青质、重胶质分子聚集形成胶核,饱和烃、芳香烃、轻胶质分子形成连续相。胶质分子结构影响其胶溶性能,侧链长度适中的胶质分子,其与沥青质、芳香分互溶性好,胶溶性能优异;沥青质的聚集程度随胶质分子含量的增加而降低。芳香分、胶质分子的协同作用使沥青质、饱和烃分子稳定存在于同一体系中,因此渣油胶体稳定性取决于不同分子结构的连续性和配伍性。     

两种中东原油的减压渣油性质的研究

运用超临界流体萃取分馏技术，对两种中东原油（沙特轻质原油与阿曼原油）的减压渣油进行分离，测定与分析了窄馏分的折光指数、密度、粘度、残炭、平均相对分子质量、元素分析（C、H、S）、金属含量（Ni，V）、族组成（饱和烃、芳香烃和胶质含量）及结构组成。并与大庆、辽河原油的减压渣油分离结果进行了对比，为沙特轻质原油及阿曼原油的减压渣油的合理加工提供了重要的基础数据。     

STUDY ON THE STRUCTURE OF HEAVY OILS

ABSTRACT

The structural parameters of six heavy oils have been calculated with n-d-M, Brown-Ladner and ¹HNMR/IR method in this paper. The aliphatic H/C atomic ratio Hs/Cs i.e. x values were obtained from IR spectra combining with ¹HNMR spectra. The comparison of structural parameters calculated by ¹HNMR/IR, Brown Ladner and n-d-M methods were carried out for the six heavy oils. It is proposed that the ¹HNMR/IR method gives more precise average molecular parameters than the Brown-ladner method. N-d-M method can gives right molecular structural parameters for some heavy oils with lower molecular weight, but the information of molecular structure obtained by it is limited.     

一个反映重油平均分子结构的特征因数

构造了一个简单的粘重函数KL。考察了不同油品和纯烃的KL值，认为几值对于油品平均分子结构的反映是准确的，随重油的平均相对分子质量增大而降低。对于相对分子质量近似的烃，烷烃KL值＞环烷烃KL值＞芳烃KL值；重油的平均相对分子质量和环化程度越高，KL值越小；普通原油KL值＞重质原油KL值；对于同一种原油，常压馆分KL值＞减压憎分KL值＞原油KL＞常压渣油KL值＞减压渣油KL值；随拔出深度增大，渣油见值减小。     

减压渣油及其组分热转化前后平均结构参数的变化

 以胜利减压渣油、孤岛减压渣油、大庆减压渣油为原料,在高压釜中进行热转化反应。反应温度为405 ℃,反应时间为1 h。将渣油及热转化残渣油分离成6个组分,对渣油及其组分的平均结构参数进行分析、计算。结果表明,热转化后残渣油六组分中的戊烷沥青质组分(n-C5At)的含量比原料减压渣油六组分中的戊烷沥青质组分含量明显增加,其他组分（F1~F5）的含量均比原料减压渣油中相应组分的含量有所降低。热转化残渣油中各组分的相对分子质量、H/C摩尔比及总碳原子数均比原料渣油中相应的组分降低。而热转化后残渣油各组分的缩合指数和芳碳率比原料渣油中的要高。     

A Geochemical Framework for Understanding Residue Properties

Crude oils, and the residual fractions thereof, vary widely in many relevant properties. Thus, a detailed characterization of a single residue stream or even a number of residue streams from one region may not be very relevant in a different part of the world. We have therefore attempted to develop a framework for understanding residue properties in a generic fashion. A detailed analysis of 11 vacuum residue fractions from a wide variety of crude oils resulted in a general model for understanding the composition and processability of residue streams. This model is based on the geochemical origin (kerogen type) and the maturity of the crude oil. The different origin of kerogen I (paraffinic) residues, compared with the more conventional kerogen II residues, is reflected in a large number of properties and also in a larger variability in these properties. However, upon maturation, the average properties of kerogen I residues and kerogen II residues converge so that mature residues of both kerogen types have much in common (low S content, low metals content, high H/C ratio etc). Maturation is found to have a negative effect on the stability and coking tendency of the residue fraction. NMR data reveal that the asphalthenes become more aromatic upon ageing, whereas the maltenes (non-asphalthenes) become less aromatic, thus causing an increasing gap in aromaticity between these fractions. Significant differences in asphaltene molecular structure between kerogen I and kerogen II residues were observed. The analytical data suggest that the concept of kerogen type and maturity may be a useful tool in describing and understanding residue characteristics and assist in optimizing feedstock selection for residue conversion processes and other residue applications (fuel oils, bitumen), as well as in understanding fouling and coking phenomena. Further research is required to establish the trends shown in this paper.     

PHYSICO-CHEMICAL AND COMPOSITIONAL ASPECTS OF BITUMEN BEARING CRUDES AND THEIR INSTRUMENTAL CHARACTERISATION

In India the production of bitumen is primarily based on middle-east crude oils which normally have a right balance of bitumen constituents (i.e. asphaltenes and maltenes). In general, bitumens obtained from such crude oil sources have a good balance of rheological and physico-chemical properties at both low and high temperatures.

Bitumen is a complex mixture consisting of compounds ranging from non-polar aliphatic and naphthenic hydrocarbons to highly polar aromatic molecules containing heteroatoms such as oxygen, nitrogen, and sulfur; and, several attempts have been reported to fractionate and characterise bitumens into broadly defined compound groups. The separation method adopted in the present study is based on the polarity of the constituent compounds comprising the bitumen. The separated groups of compounds which progressively increase in their polarities are saturates, aromatics, resins and asphaltenes. In the present study three important (middle-east) bitumen bearing short residues have been selected and their detailed physico-chemical as well elemental compositions have been reported. Each short residue has been characterised by NMR and FT-IR spectroscopy methods and the information obtained from these analyses have been used to estimate several average structural parameters. Ultimate compositions have been determined for deducing the average molecular formulae.     

渣油亚组分及其形成的胶粒颗粒尺寸的研究

 根据球形分子模型，采用特性粘度法和密度法计算了渣油亚组分(沥青质、胶质、芳香分)分子的颗粒直径；构筑了渣油中沥青质胶粒(胶团)模型，并据此计算了沥青质胶团尺寸。结果表明，采用特性粘度法，溶剂胶党性对测定沥青质大分子直径有影响，以甲基萘和苯为溶剂测定选择性粘度，关联出的沥青质分子直径分别为3.52~4.34nm和3.93~4.96nm。采用密度法计算得到的沥青质分子颗粒直径为2.39~2.79nm。大分子缔合作用对测定分子颗粒尺寸有影响。采用两种方法计算胶质、芳香分小分子颗粒直径均不受影响，分别约为1.60nm和1.25nm。渣油亚组分构成的胶团颗粒随着加氢处理深度的增加呈变小的趋势，73.3%质量分数的沥青质大分子转化成小分子。     

催化裂化气体烃收率关联模型

在小型固定流化床反应装置上进行蜡油和渣油催化裂化反应试验，经参数估计确定关联模型参数，建立与气体＋焦炭收率、汽油收率及蜡油和减压渣油结构族组成关联的催化裂化气体烃收率关联模型。统计检验结果表明，所建模型具有较高的计算精度。     

劣质重油浅度热裂化研究

在静态试验装置上以4种重油为原料,在反应温度为T±20 ℃、反应时间为2~120 min的条件下,考察了反应温度和反应时间对减黏率和生成重油中甲苯不溶物含量的影响。结果表明：对于同一种重油,在不同反应温度条件下,随着反应时间的延长,减黏率存在最大值;对于不同性质的重油,在操作条件相同情况下,其减黏率有差异;当进一步提高操作条件的苛刻度后,劣质重油的减黏率呈现快速降低趋势,表明胶体的稳定性遭到了破坏;而提高反应温度和延长反应时间都对重油中甲苯不溶物的生成起着重要作用。     

The study of the composition of oils and structure of their components during the preliminary refining of oil feedstock with metal powders

The results of elemental analysis, determination of molecular masses, IR and ¹H NMR studies of the resin—asphaltene components, and gas chromatographic—mass spectrometric analysis of lube oils from a blend of West Siberian crude oil and the liquid products of its treatment with powders of iron and copper modified with nickel and cobalt ions are presented. The structural—group analysis has been performed and the structural fragments of the average asphaltene and resin molecules have been described. The changes in the structural parameters of their molecules under the treatment conditions and in the composition of hydrocarbons and hetero compounds of lube oils have been revealed. It has been shown that the preliminary upgrading of the petroleum feedstock decreases the concentration of heteroatoms in the composition of the resin—asphaltene components and the concentration of heteroatoms and aromatic hydrocarbons the lube oils.