Optimization of chemical demulsifications of water in crude oil emulsions

The instability of the water in crude oil emulsion and separation of the dispersed water as free water are influenced by the emulsion properties and the operating parameters during the demulsification process. This study aims to relate these properties/operating parameters to the amount of separated water. Steps were taken to determine and validate the optimal separations that can be achieved. Six operating parameters were identified through sensitivity analyses to have an energetic effect on percentage water separation. The bottle test method was used on two different samples of water in oil synthetic emulsions (sample A and B from different Nigerian oil fields). Response surface methodology central composite design (RSMCCD) was used to design the experiment, and generate the desired regression equations/models. Results show that optimum percentage water separations of 93 and 95% (V/V) were achieved with the emulsions A and B respectively using the combination of the optimal variables derived from the model equations. These were improvements from percentage water separations of 80 and 83% (V/V) achieved using the two crude oil samples in their naturally occurring state when the properties of the emulsions were not enhanced to their determined optimal operating conditions.     

Determination of water content in crude oil emulsion by LF-NMR CPMG sequence

Transverse relaxation times (T2) and T2 spectrum for crude oil emulsions with different water content are obtained by low field nuclear magnetic resonance Carr-Purcell-Meiboom-Gill sequence and various methods to determine the water content are investigated. The results show that there are three methods to accurately determine the water content. When water content is greater than 20.0wt%, determination through T2 value of emulsions is fastest with the relative error below 2.5%. T2 spectrum show the characteristics of multiple peaks, and T2 value of the peaks originated from water are suitable for determination of water content for O/W emulsions. A method is developed and optimized to determine the water content by using the peak-area ratio in T2 spectrum, which is not limited by the water content and the form of emulsion.     

芳烃油中芳香分含量测定方法的考察与对比

通过对4种测定石油馏分油中芳香分含量方法的考察与测定结果等全面分析对比认为：由于每种方法的适用范围、约束条件及分析过程各不相同，测定结果自然不同，并且差异较大。综合考虑多方面的因素，建议采用《石油沥青组分测定法》对作为沥青调和组分的芳烃油进行芳香分含量测定。     

三元复合驱中乳化作用对提高采收率的影响

评价了不同机械搅拌力、不同含水率条件下,碱、表面活性剂、聚合物溶液与原油间的乳化能力,研究了这种三元复合驱过程中形成的乳化液类型及其稳定性,给出了油水比、化学剂类型、浓度、外力及其综合作用对产生乳化的影响程度。分析了大庆油田三元复合驱矿场试验中采出液产生乳化的原因。室内物理模拟实验表明,三元复合驱过程中产生的原油乳化作用是提高驱油效率、扩大波及体积的关键因素。     

原油包裹体中芳香烃组分类型与成熟度关系——以三肇凹陷扶余油层为例

为了明确油包裹体中芳香烃组分与原油成熟度的关系,基于原油的荧光性,利用单个包裹体组分无损分析的荧光光谱方法,对松辽盆地三肇凹陷扶余油层油包裹体荧光光谱进行了定量化描述。首先获取了储层油包裹体荧光颜色类型,然后获得了单个油包裹体荧光光谱图,并对比标准芳香烃在波长为365 nm单色光激发下的荧光光谱主峰波长特征值,最终划分了油气充注幕次及不同幕次油包裹体芳香烃组分类型。研究结果表明:扶余油层发育黄色、黄绿色、蓝绿色和蓝色4种荧光颜色油包裹体,代表了不同成熟度的油气充注。其中第1幕黄色荧光油包裹体主峰对应的波长(λ_max)为576.0～584.5 nm,为低成熟度油充注;第2幕黄绿色荧光油包裹体λ_max为528.7～546.3 nm,为中等成熟度油充注;第3幕蓝绿色荧光油包裹体λ_max为491.6～516.1 nm,为中等成熟度油充注;第4幕蓝色荧光油包裹体λ_max为440.6～456.5 nm,为高成熟度油充注。综合判定得出,三肇凹陷扶余油层在地质历史时期经历了4幕油气充注。油包裹体中芳香烃组分主要有十...     

Incidence of polycyclic aromatic hydrocarbons in vegetable oil blends

The consumption of extra virgin olive oil has been growing in Brazil over the years. However, as it is an expensive product, many consumers tend to substitute extra virgin olive oil with a cheaper alternative, such as vegetable oil blends (mainly a mixture of olive and soybean oils). In the preset study, different brands of oil blends were evaluated for the occurrence of 13 polycyclic aromatic hydrocarbons. The method involved liquid–liquid extraction with hexane and N,N-dimethylformamide, followed by clean-up by SPE with C18 cartridges. Analyses were carried out by HPLC with fluorescence detection. PAHs were detected in all samples analyzed and the mean sum ranged from 2.59 μg/kg to 85.30 μg/kg. A high variability in PAHs levels between brands and between different batches of the same brand was observed. Approximately 50% of the samples were in disaccording with the maximum permitted levels for BaP and PAH4 established in the Brazilian and/or European regulations.     

Origin and occurrence of crude oil in the Niger delta, Nigeria

Ten crude oils samples from onshore and offshore Niger delta were characterized based on their biomarkers and isotopic composition by Gas chromatography–Mass spectrometry and Isotope mass spectrometry. Abundance of pentacyclic triterpanes of hopane and oleanane skeletons and C₂₇–C₂₉ steranes in the oils indicates that they were formed from a mixed source (marine and terrestrial kerogen). The oleanane concentrations permit source grouping of the oils into three families.Various maturity parameters computed for the oils, especially those of aromatic biomarkers and aromatic sulfur compounds (thiophenes) to some extent reveal an increasing thermal maturity with increasing reservoir depths. The carbon isotope values lacked sufficient variation to distinguish maturity differences in the oils. This observation is quite revealing in that oils whose associate gases had earlier revealed a consistent increase in maturity with increasing depths, also have similar maturity values.The implication of this is that the oils and associated gases might have been formed at different levels of thermal maturity before being pooled together during migration into their present habitat.     

东濮凹陷西斜坡地区原油成熟度研究

采用GC-MS分析技术分析了东濮凹陷西斜坡胡状集和庆祖集油田原油芳烃化合物的成熟度参数,包括烷基二苯并噻吩(MDBT)系列、脱羟基维生素E和三芳甾烷(TAS)系列化合物.分析结果表明,芳烃化合物分布特征、脱羟基维生素E的β/γ异构体比值、4-/1-MDBT值、4,6-/1,4-DMDBT值、C₂₀/(C₂₀+C₂₆)TAS值以及三芳甾烷的相对含量,均反映东濮凹陷西斜坡二台阶构造带内的原油为烃源岩低熟阶段的产物,而长垣断层断裂带和长垣断层下降盘的原油属于烃源岩成熟阶段的产物.     

塔河油田奥陶系原油芳烃地球化学特征

芳烃化合物是原油中重要的组分,在判识原油生源环境和成熟度方面应用广泛.塔河油田主体区奥陶系原油遭受过强烈的生物降解作用,常用的饱和烃生物标志化合物指标往往不能正确反映原油成熟度、运移等信息,芳烃化合物能有效抵制生物降解作用,可更好地反映这些地质信息.通过芳烃GC-MS分析,表明塔河奥陶系原油具有高萘、高菲、高硫芴、低氧芴、低联苯等特点,均来自同一油源,生烃母质属还原-强还原环境.烷基萘指数、二苯并噻吩和三芳甾烷等成熟度指标表明,塔河油田奥陶系原油成熟度由西向东、由北向南不断增高,反映出奥陶系油气主要来自沙雅隆起东南部的满加尔坳陷.     

芳烃参数重建原油成熟度及其在哈山地区的应用

原油成熟度由于不能采用实验方法直接测定,多利用生标物参数进行判识。常用的生标物成熟度参数多为定性分析,且不适用于高成熟阶段的原油样品。以低热演化程度的烃源岩样品为研究对象,通过进行高温热模拟实验,分析了不同热演化阶段下液态烃产物的芳烃特征,探讨各芳烃参数与实测热成熟度的关系。结果显示,甲基菲、三甲基萘等参数与热成熟度具有较好的相关性,据此建立了各参数与热成熟度的拟合公式;并对哈山地区油砂样品进行了成熟度判识,其中二叠系、三叠系和侏罗系原油成熟度较低,白垩系原油成熟度较高。     

Influence of surfactants used in surfactant-polymer flooding on the stability of Gudong crude oil emulsion

The influences of an anionic-nonionic composite surfactant and petroleum sulfonate, used in surfactant-polymer flooding in Shengli Gudong oilfield, East China, on the interfacial properties of Gudong crude model oil and synthetic formation water was studied by measuring interfacial tension, interfacial viscoelasticity and Zeta potential. The influence of the surfactants on the stability of Gudong water-in-oil (W/O) and oil-in-water (O/W) emulsions was evaluated by separating water from the W/O emulsion and residual oil in the aqueous phase of the O/W emulsion respectively. The results showed that the two kinds of surfactants, namely anionic-nonionic composite surfactant and petroleum sulfonate, are both able to decrease the interfacial tension between the oil phase and the aqueous phase and increase the surface potential of the oil droplets dispersed in the O/W emulsion, which can enhance the stability of the W/O and O/W crude oil emulsions. Compared with petroleum sulfonate, the anionic-nonionic composite surfactant is more interfacially active and able to enhance the strength of the interfacial film between oil and water, hence enhance the stability of the W/O and O/W emulsions more effectively.     

O/W型TR-02稠油乳状液的配制及静态稳定性评价

针对河南油田L131井稠油,采用自制的TR-02乳化剂,根据稠油乳化降黏原理及O/W型乳状液的形成机制,研究了乳化剂的类型和含量、乳化方式、搅拌方式和搅拌速度、相体积分数等对O/W型稠油乳状液稳定性的影响,特别是初步探讨了在TR-02中加入纳米助剂TR-23,对O/W型稠油乳状液稳定性的影响,为纳米材料在稠油乳化降黏中的应用提供一个可参考的基础数据。     

松辽盆地原油芳烃分布、组成特征与原油类型划分

通过色谱-质谱(GC-MS)分析,松辽盆地黑帝庙、萨尔图、葡萄花、高台子、扶余油层原油共检测到萘、菲、、联苯、芴、二苯呋喃、二苯并噻吩、三芳甾等11个系列164种芳烃化合物。其中,黑帝庙、萨尔图油层原油主要由三芳甾类化合物和菲系列化合物组成,葡萄花油层原油主要由菲系列和系列化合物组成,高台子、扶余油层原油主要由菲系列、系列和三芳甾类化合物所构成。菲系列、系列和三芳甾类化合物在纵向上的分布,均以葡萄花油层为拐点,由浅层黑帝庙油层至深层扶余油层,菲系列、系列呈现了由低变高的趋势,三芳甾类表现了由高变低的趋势。根据三芳甾含量、三芳甾类/菲系列、二甲基菲/三芳甾烷的组合关系,松辽盆地原油可划分为黑帝庙、萨尔图油层高三芳甾类原油,高台子、扶余油层低三芳甾类原油和葡萄花油层痕量三芳甾类原油。松辽盆地原油含有三芳甾类化合物和二苯并噻吩/菲很小,表明松辽盆地烃源岩主要形成于淡水-微咸水湖相的弱氧化环境。     

哈拉哈塘凹陷奥陶系原油芳烃生物标志物特征及油源

哈拉哈塘凹陷是近些年的勘探热点地区,为了进一步明确其原油母源输入、沉积环境、成熟度和可能烃源层,对26个哈拉哈塘凹陷和塔河奥陶系原油样品、4个台盆区烃源岩样品进行了系统的芳烃生物标志物分析。研究结果表明,哈拉哈塘原油均具有高萘、高菲、低联苯、贫1,2,5-和1,2,7-三甲基萘而富1,3,6-三甲基萘、高4-MDBT/DBT和（2+3）-MDBT/DBT比值、轻芳烃碳同位素的特点,与塔河奥陶系原油非常相似,反映出其属于典型的海相成因,且以低等藻类和细菌占生源优势。高丰度的二苯并噻吩和较低的DBT/P、Pr/Ph比值,指示其源岩沉积于强还原的碳酸盐沉积环境。等效镜质体反射率R_c1和R_c2揭示哈拉哈塘原油成熟演化处于中等-较高范畴。甲基三芳甾烷异构体组成型式对比表明,中-上奥陶统烃源岩与哈拉哈塘和塔河奥陶系原油对比良好,推测其为本区奥陶系原油的烃源层。     

The impact of lactic acid bacteria with antimicrobial properties on biodegradation of polycyclic aromatic hydrocarbons and biogenic amines in cold smoked pork sausages

The influence of surface treatment with lactic acid bacteria (LAB), previously cultivated in an alternative substrate, on the formation of polycyclic aromatic hydrocarbons (PAHs) and biogenic amines (BAs) in cold smoked pork meat sausages was investigated. Moreover, sausages treatment with LAB after the smoking on PAHs content changes was evaluated. Additionally, the inhibitory effects of LAB metabolites on food spoilage bacteria was determined using the agar well diffusion assay method. The metabolites of Pediococcus acidilactici KTU05-7, Pediococcus pentosaceus KTU05-9 and Lactobacillus sakei KTU05-6 strains showed good inhibitory properties against tested pathogenic and food spoilage bacteria. Moreover L. sakei produced bacteriocins inhibited the growth of Pseudomonas aeruginosa and Escherichia coli. Furthermore, the treatment of sausages surface with LAB before smoking decreased the content of cadaverine and spermidine, whereas the treatment of sausages surface with LAB after smoking decreased the content of putrescine (approx. 53% when L. sakei and P. acidilactici were applied) or totally eliminated (applying P. pentosaceus) from outer layers and centre of sausages. The application of LAB for sausages treatment before and after smoking significantly decreased both benzo[a]pyrene and chrysene decreasing (p < 0.05). The results also confirm that potatoes juice could be used as an alternative substrate for LAB cultivation, and the obtained fermented bioproducts could be applied for surface treatment of cold smoked pork sausages in case to reduce microbial contamination, and PAHs content in final product.     

Effect and prediction of aromatic oil on swelling degree of direct-to-plant SBS modifier in bitumen

The effects of aromatic oil on the swelling degree of the modifier in bitumen were analyzed from macro and micro perspectives. The evaluation indicator of swelling degree was put forward and the prediction model of swelling degree was established. The result shows that the swelling degree of direct-to-plant SBS modifier in bitumen can be evaluated by the structure fineness of SBS after swelling. There is an optimal content of aromatic oil makes the direct-to-plant SBS has the best swelling degree. The swelling degree determines the performances of the direct-to-plant SBS modified bitumen to a certain extent.     

Calculating single layer production contribution of heavy oil commingled wells by analysis of aromatic parameters in whole-oil GC-MS

Traditional fluid production profile logging is not usually suitable for heavy-viscous crude oil wells.Biodegradation of heavy oil can lead to the loss of n-alkanes,and the use of chromatogram fingerprint techniques in studying the production contributions of single layers in heavy oil commingled wells has limitations.However,aromatic compounds are relatively well preserved.We took the heavy oil commingled wells of small layers NG55 and NG61 in the ninth area of the Gudong oil field as examples.Based on the principle of chromatography,the whole-oil GC-MS was used,and the aromatic parameters which have a strongly linear relationship with the ratio of mixed two end member oils were verified and selected in laboratory.Studies showed that the ratio of （1,4,6-＋ 2,3,6-trimethylnaphthalene） to 1,2,5-trimethylnaphthalene has a strongly linear relationship with the ratio of the mixed two end member oils （R2=0.992）.The oil contributions from single layers NG55 and NG61 in six commingled heavy oil wells were calculated using established charts and this relationship.The calculated results are consistent with the results of long period dynamic monitoring and logging interpretation in the study area and can provide a scientific basis for monitoring production performance and hierarchical management of reservoirs.The study provides a new geochemical method for calculation of the contributions of single layers in heavy oil commingled wells when conventional fluid production profile logging is not suitable.     

海洋沉积物中芳香烃预测中国南海潮汕坳陷油气圈闭方法

利用一种先进的地球化学勘查技术,通过检测海底沉积物中的芳香烃的含量预测可能的油气圈闭。基于新的高分子吸附材料快速高效地提取海洋表层沉积物中痕量的苯、甲苯、乙苯和二甲苯（简称为BTEX）和萘、菲、蒽（简称为PAHs）等芳烃组分,结合热脱附和气相色谱质谱（GC-MS）完成对沉积物中痕量BTEX和PAHs的定性定量分析,利用BTEX和PAHs浓度异常范围预测油气圈闭。结合中国南海北部陆坡深水区白云凹陷荔湾地区已知LW3-1油气田的验证结果,以及中国南海东沙海域中生界油气勘探新区（潮汕坳陷）二维地震勘探的结果,提出了在潮汕坳陷北部斜坡区和中央隆起带、水深1 000~1 500 m的深水区是寻找中生代油气藏的重点勘探区,为缩小勘探目标区和降低勘探成本提供了重要参考。     

超亲氮化碳-硅藻土复合滤层油包水乳液快速破乳

目的实现高黏度油品油包水乳液的快速高效破乳。 方法以三聚氰胺为原料,通过热聚法制备超亲水材料氮化碳,采用制备的氮化碳混合硅藻土制备复合滤饼,通过抽滤实现高黏度油包水乳液快速破乳。 结果含质量分数为1.5 %氮化碳的0.5 cm氮化碳-硅藻土滤饼可实现水含量在6 %(w)以内,乳滴粒径在2.32 μm及以上,油包水乳液完全破乳,20 kPa真空度的破乳速率可达3.57 L/min,破乳效率为97.36%,油回收率为99.72%以上;增大破乳用滤饼厚度,可用于更高含水量乳液的破乳;破乳基于超亲氮化碳对水的强吸引力和硅藻土微孔破碎共同作用。 结论氮化碳-硅藻土滤饼可实现油包水乳液快速高效破乳,具工业实用前景。 