稠油沥青质分散剂作用机制*

为了提高馆陶、孤岛稠油的稳定性,考察了阴离子型分散剂AA(磺酸基型)、非离子型分散剂NA1(多元醇型)、油酸、月桂酸和棕榈酸对馆陶、孤岛稠油沥青质溶解度的改善效果,筛选了分别对两种沥青质稳定分散作用最好的两种分散剂NA1和AA,进一步考察了处理温度对分散剂改善效果的影响、分散剂与沥青质的相互作用方式。研究结果表明,在较低的温度下,多元醇型非离子分散剂NA1对沥青质的稳定作用显著,能够显著增大溶液中沥青质的饱和浓度;但当处理温度升高到80℃时,沥青质饱和浓度急剧下降,但仍比未添加NA1的沥青质饱和浓度高得多。而含磺酸基的离子型分散剂AA改善效果受处理温度影响较小。另外,通过红外光谱分析发现,AA的磺酸基能够与沥青质中的N—H键、O—H键之间形成红移型氢键;NA1中的羟基O—H、醚键、酯基等官能团能够与沥青质分子中的N、O、S等杂原子以及芳香共轭π键形成蓝移型氢键。两种分散剂与沥青质的相互作用方式均为与沥青质分子通过氢键而结合。图11表3参15     

稠油油藏胶质沥青质分散技术

为解决稠油开采过程中胶质沥青质析出堵塞储层的问题,进行了稠油油藏胶质沥青质分散解堵技术研究,研制成功了稠油油藏胶质沥青质分散解堵剂.该分散剂具有极强的溶解、分散稠油中的胶质沥青质及杂环芳烃能力和抗凝固防沉降能力,在10℃低温下系统仍不会分层.注汽过程中能防止胶质沥青质沉积,疏通液体流动通道,大幅度降低注汽压力;同时可有效降低稠油黏度,提高原油在低温下的流动性,改善稠油、超稠油在井筒的举升能力及地面的集输效果.     

稠油沥青分散剂的筛选及效果研究

为解决我国西部某油田稠油开采过程中胶质、沥青质析出堵塞井筒问题,考察了沥青分散MCS,WD-06,JX-108,CL-5,XJ-2的溶解和分散性能,筛选出对堵塞物溶解效果最好的分散剂XJ-2。并考察了分散剂XJ-2对石蜡的溶解效果、热处理温度对分散剂溶解速率的影响、分散剂的最大溶解量及对稠油黏度的影响。结果表明,分散剂XJ-2具有良好的溶解蜡质堵塞物和抑制其析出的能力;当热处理温度为90℃时,溶解速率达1.713 2 mg/(m L·min);当其加量为1 000 mg/L时,原油黏度大幅下降。现场应用表明,该分散剂可有效防治胶质、沥青质沉积造成的堵塞。     

沥青质分散剂与阻聚剂研究进展

沥青质作为石油中极性最大、最重的组分,极容易发生絮凝沉降,给石油的开采、储运及加工带来困难,而添加化学添加剂是阻止和解决沥青质絮凝沉积的最有效方式之一。从化学添加剂的分类、结构特征、作用机理及效果等方面综述了近十年来沥青质化学添加剂的研究进展,并分析了影响沥青质化学添加剂作用效果的因素,对沥青质化学添加剂的选用及合成提出了一些建议。     

环烷酸对高沥青质含量稠油乳状液稳定性的影响

以高沥青质塔河稠油为研究对象,从中分离出沥青质,配制成模型油乳状液;从辽河、苏丹原油中分离出天然羧酸,考察原油中天然羧酸对塔河沥青质模型油乳状液稳定性的影响。 结果表明,天然羧酸可以起到类似于胶质的作用,通过对沥青质的分散作用,降低沥青质模型油乳状液的稳定性。 有机羧酸和烷基芳磺酸可以起到与天然羧酸类似的作用,而且烷基芳磺酸降低模型油乳状液稳定性的能力更强。     

新型油溶性沥青质分散剂抑制重质原油沥青质沉积的研究

针对新疆重质原油沥青质沉积严重的问题,以聚异丁烯丁二酸酐、苯胺和对氨基苯酚为原料合成了尾部基团为高度枝链化的聚异丁烯基,头部基团分别为苯基及酚羟基的新型油溶性沥青质分散剂PA1和PA2。采用分光光度法与显微镜法评价了所合成分散剂对沥青质沉积的抑制效果。实验结果表明,分散剂PA2抑制沥青质沉积作用效果优于PA1。通过对分散剂PA2抑制沥青质沉积作用效果的评价,确定了最佳合成条件：对氨基苯酚与聚异丁烯丁二酸酐摩尔比为1.2,反应温度为120 ℃,反应时间为6 h。在分散剂PA2加入量为200 mg/L的条件下可以将新疆重质原油的初始絮凝点由-19.87提高到8.63,显著改善了新疆重质原油稳定性。     

沥青质分散剂评价方法改进与新型高效分散剂合成

为了更加高效准确地评价沥青质分散剂,首次利用测定掺稀后黏度变化的实验方法取代现有沉淀评价方法,结合对现有市售分散剂的评价结果,分析了原有方法的缺点与不足。利用新方法探索了不同基团、链长、结构对分散剂分散性能的影响。结果表明,在用沉淀法测定时,强极性的烷基苯磺酸和长链离子液体分散剂出现增稠现象。针对塔河某掺稀井最为合适的沥青质分散剂应是具有C18烷基链长、含有2~4个极性头基团的多胺类非离子型表面活性剂。在此基础上,以油酸和二乙烯三胺合成了新型的长链烷基酰胺二胺型沥青质分散剂。通过掺稀黏度法测得,新合成的分散剂与沥青混合液在30、60℃下的平均黏度为890和277 mPa·s,比常用的Span80多元醇类分散剂分别提高27%和46%。     

无机盐对沥青质稳定性及对分散剂性能的影响

诱发沥青质沉积因素众多,而无机盐及矿物对沥青质稳定性的影响及其与沥青质之间的作用机理尚不明确。针对4个存在沥青质沉积问题油区的原油和沥青质沉积物样品,采用四组分分析、高温模拟蒸馏、傅立叶变换红外光谱和X射线荧光能谱等测试方法,对原油组分组成和元素以及沥青质沉积物元素和水溶液物性参数分别进行了测定和分析,并评价了无机盐对沥青质分散剂性能的影响。实验结果表明：原油样品A发生沥青质沉积是由于原油中含有不稳定沥青质簇,胶体不稳定指数CII 值达到1.1。而原油样品B和C则是由于原油被钻完井液污染所致。原油及沥青质沉积物样品中大部分无机元素来源于储层环境,而Br元素则来源于钻完井液中的溴化盐。无机溴盐能够与沥青质分子产生离子-离子或离子-偶极的强引力作用,破坏原油中胶体稳定性。无机盐浓度的降低会削弱无机盐离子对沥青质和分散剂分子之间相互作用的干扰,大幅提升分散剂性能。研究成果可为预防沥青质沉积、缓解沉积伤害提供了参考和借鉴。     

塔河油田稠油沥青质解堵技术研究与应用

塔河油田油藏原油高含沥青质,随着油井生产,油藏、井筒压力、温度场的变化,井筒堵塞现象时有发生.采用X射线荧光光谱、组分分析、溶剂萃取等方法分析了堵塞物成分.结果表明,堵塞物90%以上是有机物,有机物中沥青质含量大于38%.针对堵塞物主要组分,研制了新型沥青解堵剂,对其性能进行了评价.60 ℃时溶解速率最高可达到2.956 mg/(mL·min),胶体不稳定指数大于0.9的原油中加入质量分数1%新型沥青解堵剂,可有效抑制沥青质沉积.     

塔河油田沥青质稠油成因分析及防治技术

塔河油田TK235、TK305等井陆续出现沥青质稠油沉积堵塞油管造成停产,对生产造成了严重影响。针对此类问题,文中对塔河油田原油中沥青质的沉积问题进行了综合研究,形成了有效的沥青质稠油沉积堵塞防治技术。通过对塔河油田沥青质原油组分进行分析,结合沥青质沉积堵塞物成分的分析,发现沥青质沉积主要是由于原油组分在举升过程中的环境条件变化所导致,从而开发了掺稠油、掺改性稠油（稠油＋沥青分散稳定剂）等治理工艺．试验结果表明：这些工艺较好地解决了沥青质沉积堵塞油管的问题,实现了油井的正常生产,并在现场应用中取得了良好的效果。     

委内瑞拉稠油沥青质的XPS研究

以委内瑞拉稠油沥青质为原料,采用X射线光电子能谱（XPS）定性和定量分析了沥青质表面含碳、氧、氮、硫官能团结构和含量。结果表明,委内瑞拉稠油沥青质表面的碳原子主要以C-C和C-H形式存在,约5%的碳原子与氧原子结合;含氧官能团中羰基为主要含氧结构,其氧原子数量占氧原子总数量的44%左右,C-O和COO的氧原子数量分别占氧原子总数量的29%和27%;含氮官能团中,约59%的氮为弱碱性或非碱性的吡咯类氮,剩余为强碱性的吡啶类氮;含硫官能团中,脂肪类硫约占57%,其余为噻吩类硫。从委内瑞拉稠油沥青质表面杂原子官能团摩尔数量来看,羰基摩尔分数最多(>1%),其次是吡咯氮和脂肪硫(均约1%),C-O基、羧基、吡啶氮和噻吩硫摩尔分数基本相同（均约0.7%）。     

The Effect of Solvent Nature and Dispersant Performance on Asphaltene Precipitation from Diluted Solutions of Instable Crude Oil

Abstract

The asphaltene precipitation experiments were studied on El Furrial crude oil from western Venezuela, which is known to exhibit serious instability problems. A Turbiscan backscattering apparatus was used to evaluate the precipitation of asphaltenes with different solvents. The transmittance variation with time was studied as the crude was diluted with heptane, pentane, and cyclohexane. Linear alkanes-containing systems exhibit a two-stage behavior, whereas only one is found when diluting with cyclohexane. Dispersing agents were tested by using the precipitate height as a criterion of effectiveness. Results are reported for ethoxylated nonylphenols and a commercial dispersant.     

原油中沥青质的稳定性及其影响因素

：影响原油中沥青质稳定性因素多且复杂,而原油组分组成变化对沥青质稳定性的影响机理尚不明确。在 测定10 种不同原油油样密度、黏度、元素组成和四组分（饱和烃、芳香烃、胶质和沥青质）含量的基础上,采用场发 射扫描电镜、傅立叶变换红外光谱、X射线荧光能谱和Zeta 电位评估等方法,研究了10 种原油油样的组分组成及 其与沥青质之间相互作用特征,明确了蜡、水和无机盐对沥青质稳定性的影响。研究结果表明,原油的密度和黏 度与重烃、轻烃含量之比呈正比,当沥青质含量增加时,原油中H含量和H、C物质的量比降低,非烃含量增加,沥 青质的稳定性降低。蜡和水会改变原油组分组成,影响沥青质稳定性。原油中无机、有机金属含量分别介于 0.0021%～0.0814%和0.0007%～0.0655%。钒和镍等有机金属会破坏沥青质的稳定性,而储层中无机金属则会 增强沥青质稳定性。沥青质沉积物表面存在大量带负电荷的无机微粒,导致其水溶液的Zeta 电位值为负。当 Zeta 电位绝对值越大时,沥青质的稳定性更好,说明由无机微粒产生的电荷可以稳定原油中的沥青质,降低沥青 质的聚集倾向。研究成果为有效预防沥青质沉积、缓解沉积伤害提供了参考和借鉴。     

Crude Oil Blending Effects on Asphaltene Stability in Refinery Fouling

Abstract

It has been known for some time that blending of incompatible crude oils may lead to asphaltene destabilization. The link between such asphaltene destabilization and their subsequent fouling of equipment in refinery operations was established in this study. Several refinery crude blends known to cause problems ranging from desalter upsets to fouling in pre-heat train were studied. Stability analysis of the crudes and their blends using a solvent titration method with a laser-based solids detection system showed that destabilization of the asphaltenes is caused, in the main, by blending of incompatible crudes. The stability data showed that the individual crudes had a high, medium, or low fouling potential. The blends of those that are incompatible however showed increased instability and may be the cause of the fouling problems encountered in the pre-heat train heat exchangers during their processing.     

Crude Oil Blending Effects on Asphaltene Stability in Refinery Fouling

It has been known for some time that blending of incompatible crude oils may lead to asphaltene destabilization. The link between such asphaltene destabilization and their subsequent fouling of equipment in refinery operations was established in this study. Several refinery crude blends known to cause problems ranging from desalter upsets to fouling in pre-heat train were studied. Stability analysis of the crudes and their blends using a solvent titration method with a laser-based solids detection system showed that destabilization of the asphaltenes is caused, in the main, by blending of incompatible crudes. The stability data showed that the individual crudes had a high, medium, or low fouling potential. The blends of those that are incompatible however showed increased instability and may be the cause of the fouling problems encountered in the pre-heat train heat exchangers during their processing.     

Stability of Water-in-Crude Oil Emulsions: Effect of Oil Aromaticity,Resins to Asphaltene Ratio,and pH of Water

Abstract

The formation of tight water-in-oil emulsions during production and transport of crude oils is a great problem challenging the petroleum industry. Tremendous research works are directed to understanding the mechanism of formation, stabilization, and controlling of oil field emulsions. This article presents experimental results of some of the factors controlling the formation and stabilization of water-in-crude oil emulsions. In this study, asphaltenes and resins separated from emulsion samples collected from Burgan oil field in Kuwait have been used to study emulsion stability. Model oils of resin to asphaltene ratio of 5:1 and toluene-heptane mixtures have been used to study the effect of oil aromaticity on emulsion stability. Results indicate that at low toluene content (below 20%) or high content (above 40%) less stable emulsions are formed. At a threshold value of 30% toluene, a very tight model oil emulsion is formed. The effect of resins to asphaltene (R/A) ratio on stability of model oil has also been investigated. Results reported in this paper show that as the R/A increases the emulsions become less stable. The effect of pH on stability of model oil emulsion made of 50/50 heptane-toluene mixture having R/A ratio of 5:1 have been studied. Experimental results revealed that as the pH of the aqueous phase of model oil increased from 2 to 10, the emulsion became less stable. At high pH, the asphaltene particles are subjected to complete ionization leading to destruction of the water-oil interface and eventually breakdown of the emulsion.     

胜利稠油水热裂解过程中沥青质结构特征的变化分析

为了阐明在双亲性催化剂的条件下,在250 ℃和280 ℃下稠油水热裂解反应对稠油沥青质分子结构及稠 油黏度的影响,以胜利稠油为研究对象,使用C₁₂BSNi为催化剂,通过使用FT-IR 和1HNMR等手段分析水热裂解 反应前后沥青质分子结构的变化。研究结果表明,稠油在250 ℃下发生水热裂解反应后,黏度大幅降低,降黏率 可达到60.4%,但随着反应温度升高到280 ℃时,反应后的降黏率降至53.8%。随水热裂解反应温度从250 ℃升 高到280 ℃,稠油沥青质分子平均侧链长度逐渐减小,然而芳香度不断增加,芳环数量增多,说明沥青质分子发 生了自由基缩合反应,沥青质平均分子结构变大,导致降黏率相对减小;此外,沥青质分子在反应过程中发生一 系列的断键反应,导致其空间位阻减小,且沥青质分子单元片层越小越容易发生堆积。通过SEM观察到,随温 度升高,沥青质的孔道逐渐变大并且更加密集,但表面聚集颗粒变大。本文研究对稠油水热裂解反应操作条件 的优化有重要的指导意义。