碱-表面活性剂-聚合物(ASP)三元复合体系乳化性能影响因素的探究

ASP三元复合体系的乳状液稳定性是影响石油采收率的重要因素之一。通过从表面活性剂、碱、聚合物3个角度进行分析发现,当表面活性剂的疏水基团与原油结构相近时,乳化性能最好,乳化稳定性和表面活性剂浓度呈现正相关关系,超过临界值后趋于稳定;碱可以和原油中的酸性物质发生反应生成乳化剂,加强乳化性能;聚合物分子和原油乳化后会形成强度较大的界面膜,对稳定性增加起到促进作用。上述研究不仅推进了ASP三元复合体系乳化性能的研究,更为推进新型三元体系提供了理论基础。     

ASP三元组分的残留对破乳过程动力学参数的影响

针对单一组分及ASP三元组分存在的两种不同乳液体系,以排液时间td、半生命期t1/2及破裂速率常数k为考核指标,采用单滴法研究了原油采出液中的残留组分聚合物、碱及表面活性剂的含量对破乳过程动力学参数的影响。结果表明:ASP三元组分的残留对动力学参数的影响呈现出一定的规律,其中,聚合物是使三元复合驱油体系破乳难度增大的主要因素,在含聚合物的乳液体系中,破裂速率常数比含碱和含表面活性剂体系小一个数量级,而碱与表面活性剂对破乳的影响与这两种组分的残留量有关。     

油田原油破乳剂的作用机理及应用

原油作为我国重要的战略物资,因而其开采备受社会所瞩目。原油在天然表面活性剂的作用下会与水形成稳定的乳化液,这对于原油的提炼开采构成一定的影响,乳状液稳定性越强,破乳难度越大,原油开采提炼难度越大。由此各种原油乳状液破乳技术不断被研究开发并投入到实践应用。对此,从原油破乳剂的作用机理、影响乳状液稳定影响因素等方面进行分析,对原油破乳剂的主要类型、应用特定和研究进展现状进行阐述,归纳总结当前原油破乳剂的研究进展。     

二元乳状液稳定性影响因素的研究

制备了聚合物/表面活性剂二元乳状液,考察了聚合物相对分子质量、聚合物质量浓度、表面活性剂质量分数、油水比(原油与聚合物/表面活性剂二元乳状液体积比)对二元乳状液稳定性的影响。结果表明:提高表面活性剂的质量分数和聚合物的质量浓度,采用相对分子质量较低的聚合物,降低油水比,有利于二元乳状液的稳定。     

原油乳状液化学破乳机理——锁匙说

由于原油乳状液形成及稳定性的因素复杂以及影响原油乳状液破乳的因素众多,因此,对原油乳状液的化学破乳机理提法各异,主要有顶替或置换、反相作用、絮凝-聚结、膜排液、膜击破、润湿增溶等。本文主要根据一些实验的结果和现场的破乳工作,对破乳机理提出了新的说法——锁匙说。该理论的核心主要注重破乳剂与体系的配伍性。     

重烷基苯磺酸盐驱油剂中试产品的应用性能

在1000t/a降膜式连续磺化装置上对重烷基苯的磺化进行了中试放大,结果表明中试产品质量可靠。经复配的驱油剂中试产品能在较宽的表面活性剂浓度和碱浓度范围内与大庆原油、辽河原油及苏北原油形成超低界面张力,尤其能溶于总矿化度12×104mg/L、钙镁离子质量浓度为5000mg/L～6000mg/L的中原油田地层水中,在无碱条件下使中原油田原油/地层水的界面张力降至10-2mN/m～10-3mN/m数量级。对大庆原油和苏北原油的驱油试验表明,中试驱油剂ASP(碱-表面活性剂-聚合物)体系的驱油效率比水驱提高15%～35%OOIP(原油地层储量)。     

二元复合驱采出液稳定性及破乳研究

用红岗原油、聚合物和表面活性剂配制二元复合驱模拟采出液,考察了化学剂对乳液稳定性的影响,并研究了破乳剂FPW-1的破乳性能.结果表明,聚合物、表面活性剂对乳液的稳定性均有影响,二者存在明显的协同效应,致使原油采出液更加稳定,破乳难度加剧;FPW-1破乳剂对于红岗油田二元复合驱模拟采出液具有较好的破乳性能.     

胜利孤岛注聚原油破乳剂的筛选与性能评价

以研究孤岛注聚原油乳状液破乳为目的,通过瓶试法和界面性质的测定,筛选了多种类型的原油破乳剂,考察了破乳剂质量浓度、聚合物和原油组分对破乳效果的影响,探讨了原油乳状液的破乳机理。结果表明,破乳剂BF-069质量浓度在100mg/L,50℃条件下,脱水率达到70%以上,现场温度稍微升高,脱水率达到85%左右,破乳剂BF-069已在胜利油田应用,现场使用效果良好;聚合物质量浓度在50mg/L时,原油乳状液最难破乳;原油中不同组分对破乳效果的影响不同,油水界面性质的测定表明,胶质和沥青质是影响原油破乳的主要因素。     

柴油乳状液的稳定性及热破乳研究

以柴油乳状液模拟大庆油田三元复合驱油田采出水,采用瓶试法,考察了油水体积比,碱、表面活性剂、聚合物质量浓度,剪切速率,乳化时间对乳状液稳定性的影响,得到满足试验要求的柴油乳状液。使用恒温水浴锅加热破乳,采用激光粒度和Zeta电位仪测定粒径分布和Zeta电位,紫外可见分光光度计测定破乳后的柴油浓度。结果表明,破乳后水层含油量随着温度的升高而降低,平均粒径随着温度的升高而减小,60℃时的粒径分布峰随破乳时间而延长变宽,热破乳机理主要集中在降低油滴界面膜强度和降低体系黏度两方面。     

纳米二氧化硅对表面活性剂溶液乳化性能的影响

纳米SiO_2由于其较高的比表面积,会与原油乳状液作用,改变原油乳状液的乳化能力,本文通过室内实验分析纳米SiO_2对表面活性剂溶液乳化性能的影响,研究结果表明,原油中加入表面活性剂形成乳状液后,黏度会随之增大,不同类型表面活性剂对黏度的影响存在差异;当温度较低时,乳状液中液相的尺寸较小,数量较多,乳化比较严重;而加入纳米SiO_2后,乳状液中的液滴在较高的温度下仍然能够保持较好的乳化能力,大幅度的增加表面活性剂乳状液的稳定性。     

改性碱木质素产品在三次采油中的应用研究

改性碱木质素(HML)作为牺牲剂可以显著地减少主表面活性剂石油磺酸钠ORS-41的吸附损失(减少量>50％),HML能和石油磺酸钠、碱、聚合物配合将油水界面张力降至超低范围,以0.15％改性木质素代替50％ORS-41表面活性剂,复合驱采收率可达到20％左右,略高于单纯应用0.3％ORS-41三元复合体系的复合驱采收率。改性碱木质素作为三次采油牺牲剂具有广阔的应用前景。     

三元复合驱中原油乳化作用研究

通过乳状液稳定实验考察了大庆油田碱-表面活性剂-聚合物三元复合驱过程乳状液的形成机理、乳状液类型及稳定性。结果表明,大庆原油与碱反应1d时,测得其浓相体积分数为25%,所形成的乳状液为O/W型乳状液,而随着原油与碱作用时间的增加,其浓相体积分数达到40%以上,形成W/O型乳状液,且乳状液稳定性随作用时间增加而增强。大庆原油与水溶性表面活性剂ORS-41溶液作用时,所形成的乳状液为O/W型,且乳状液的稳定性与原油和ORS-41作用时间的长短关系较小。原油与NaOH和ORS-41混合溶液作用时,形成上层为W/O型乳状液,下层为O/W型乳状液的混合体系。     

Acidic Heavy Oil Recovery Using a New Formulated Surfactant Accompanying Alkali–Polymer in High Salinity Brines

The strength of a newly formulated surfactant with an alkali and polymer (AS/ASP) to improve an acidic heavy oil recovery was laboratory evaluated by various flooding experiments. The comparative role of the parameters like chemical nature, surface wettability, salinity, temperature and injection scheme were explored at high temperature and pressure on Berea sandstone rocks. According to the results the anionic surfactant is capable of providing proper oil displacement under high salinity conditions around 15 wt%. Continuous monitoring of differential pressure response and effluents’ state clearly represented the formation of an emulsified oil in high saline solutions with both alkali and surfactant. Adding sodium metaborate to the surfactant solution reduced the interfacial tension (IFT) to ultra low values and decreased the surfactant emulsion generation capability at higher salinities. Besides, adding Flopaam AN113SH to the chemical slug increased the residual oil removal owing to lower mobility ratios. So, while high capillary number and an emulsion phase were generated by the A/S slug phases, adding polymer could further enhance the performance of these chemicals. On the other hand, chemical flooding through the oil-wet medium resulted in shorter break through time, lower differential pressure, finer emulsion formation, and lower oil recovery in comparison to the similar water-wet cases.     

水包油型乳化液油滴的管内节流破碎行为与机理

实验研究了水包油型乳化液油滴在管内节流元件处的破碎行为,分析了破碎机理. 结果表明,液滴破碎主要发生在节流元件内壁及下游附近,其概率是施于液滴上湍流应力与液滴表面能之比的递增函数,是流体韦伯数及节流元件两侧最大压差的递增函数;在湍流状态(Re>4000)下,液滴充分振荡且受到较大的水流惯性力和速度梯度剪切力,更易破碎;由苏丹红IV染色的正庚烷体系界面张力由非染色时的47 mN/m降到23.6 mN/m,黏性力对液滴破碎的影响程度下降,受流速、压差等影响的惯性力起决定性作用,液滴破碎程度更大;流速决定流体对分散相油滴的湍流剪切破碎力,流速增大则油滴粒径破裂程度加大,而流速取决于流量和节流比;注入染色正庚烷油相体积增大(0.5~5 mL),削弱了节流元件的液滴破碎作用,两相流体系倾向于形成更大直径的液滴,中位径一般为20~35 mm.     

碱、聚合物对表面活性剂吸附影响分析

油藏对表面活性剂的吸附作用,是砂岩表面化学物质与表面活性剂间相互作用的结果。ASP复配体系溶液中,碱对表活剂的吸附影响较大,在表活剂溶液中加入碱后,砂岩对表活剂的吸附量下降,且吸附量下降幅度与碱浓度成正比。实验结果表明,碱可以使粘土矿物对阴离子表面活性剂吸附量降低70%~80%,而油藏砂岩对表活剂吸附量可降低10%~40%。聚合物对表活剂的吸附影响较小,数值模拟结果表明吸附量降低15%~30%。这是由于聚合物在表活剂溶液中水解后,部分分子团带有负电荷,这就抑制了砂岩对表活剂的吸附作用;另外,加入聚合物后,复配体系溶液变稠,使得溶液扩散速率降低,减小波及体积,进而削弱表活剂吸附效果。     

The influence of NaOH on the stability of paraffinic crude oil emulsion

The alkaline–surfactant–polymer flooding using sodium hydroxide as the alkali component to enhance oil recovery at the on shore oil fields at Daqing in China has brought new problems for the oil industry. Even though, the reservoir contained paraffinic crude oil, the alkali added formed stable water-in-crude oil emulsion and de-emulsification process was necessary to separate oil and water.The problems related in the enhanced oil recovery process using the alkaline–surfactant–polymer flooding technique in the Daqing oil field have been investigated in the laboratory using fractions of Daqing crude oil. The oil was separated into asphaltene and aliphatic fractions and then used in an additive free jet oil to form model oils. The emulsion stability of each of the water-in-model oil emulsions formed between water or 0.6% sodium hydroxide solution and model oil was investigated. The interfacial properties such as interfacial tension and interfacial pressure of the systems were also measured. These in combination with the chemical nature of the fractions were used to get insight into the problem related to the ASP flooding technique using sodium hydroxide as the alkaline component.The study reveals that the sodium hydroxide solution reacts with fatty acids in the aliphatic fraction of the crude oil and/or with the fatty acids formed from the slow oxidation of long chain hydrocarbons, and form soap like interfacially active components. These accumulate at the crude oil–water interface and contribute to the stability of the oil/water emulsion.     

Geopolymer assembly by emulsion templating: Emulsion stability and hardening mechanisms

This work investigates emulsion templating to synthesize hexadecane oil/geopolymer composites. In a system with hexadecane as the internal (dispersed) phase and an alkali activated continuous phase without added surfactant, adding aluminosilicate clay particles does not increase resistance against creaming or coalescence, while adding a surfactant (L35 or CTAB) stabilizes the solid-liquid interface. Infrared studies and rheological studies of the associated geopolymerization determined that the presence of the organic phase or surfactant has no significant effect on the geopolymerization kinetics, as determined by the change in time of the Si-O-T IR stretching frequency and the rheological moduli involved during the process. The stabilization of the organic template is reminiscent of Pickering emulsion even though we employ a much greater amount of inorganic material for geopolymer formation. Although the addition of surfactant has a significant effect on the behavior of the paste, the percolation of the network remains unmodified, highlighting the fact that the phenomenon is not dependent on viscosity. Finally, rheological measurements were used to obtain the mass fractal dimension of the as-made gel network, which is able to differentiate the interfacial effect between surfactant molecules with a slightly denser interphase when a cationic surfactant is used.     

大庆油田三元复合驱采出液的油水分离特性

采用室内配制的模拟三元 (碱、表面活性剂、聚合物 )复合驱采出液研究了大庆油田三元复合驱采出液的油水分离特性 ,以模拟采出液为介质采用均匀设计方法研制了一种针对大庆油田三元复合驱采出液的破乳剂并测试了该破乳剂对模拟三元复合驱采出液和实际三元复合驱采出液的破乳效果。     

大庆油田三元复合驱采出水的稳定性及其反相破乳剂的应用

采用室内配制的模拟三元 (碱、表面活性剂、聚合物 )复合驱采出水研究了残留驱油剂含量对大庆油田三元复合驱采出水稳定性的影响规律 ,以模拟采出水为介质研制了一种针对大庆油田三元复合驱采出水的反相破乳剂FM - 3 ,FM - 3对北 1- 6 -P36井实际三元复合驱采出水 4h除油率 93 5 %。