纳米技术在提高原油采收率方面的应用

对纳米技术在提高原油采收率方面的应用作较详细的介绍和评述,其中包括由表面活性剂、低碳醇、盐水及烃组成的纳米微乳液,分子沉积膜和表面活性剂的溶致液晶体系的作用机理及提高采收率的效果;还包括微一纳米颗粒封堵技术、纳米降压增注技术、提高采收率基础理论研究等方面的应用。     

应用微生物提高原油的采收率

本文描述了应用微生物处理油井系统和油藏来控制石蜡说积物，因而达到增产和提高采收率之目的。该技术适用于溶解气驱油藏产生的石蜡基原油。这项微生物增产技术的应用能增加所有采用过储层的原油采收率。     

纳米技术提高石油采收率研究进展

纳米技术提高石油采收率是具有发展前景的“改进水驱”的新技术，总结了近年来纳米采油技术的研究进展情况，对纳米膜驱油的机理以及驱渗特征进行了简单介绍，提出了将来的发展方向。     

声场提高原油采收率研究

该文用实验方法研究了声场提高油采收率的机理。研究表明，声场对解除油层伤害造成的固体堵塞，消除贾敏效应及改善孔隙附面层均有一定作用，由于油层解堵，提高了水驱油波及系数及原油采收率，在所给实验条件下，经声场处理的含油岩心，水驱油采收率可提高６％～１７％，现场应用例子也取得了良好效果。     

注浓硫酸提高原油采收率

本文阐述了原苏联注浓硫酸提高原油采收率的室内研究和矿场试验结果。1971～1986年的15年期间,原苏联鞑靼油田总共通过491口注入井向油层注入了44.84万t硫酸。据原苏联的报导,所有注硫酸的井,至今没有发现硫酸突进到采油井井底现象,也没有发现采出原油的质量有明显变化,而注硫酸的经济效益也很高。计算表明,注一吨硫酸可增产150～200t原油,注入成本只占收益的1％左右。本文还引述了注浓硫酸提高采收率的机理、应用条件和注硫酸工艺及防腐措施。本文认为注浓硫酸提高原油采收率的方法是可行的,硫酸的腐蚀问题不是该项技术应用的障碍,并建议石油天然气总公司组织开展硫酸驱油的研究。     

提高原油采收率的电动力学新方法

利用直流电场来提高原油采集收是９０年代以来受到重视的提高采收率新方法，在多次现场试验中的均取得了很好的效果。其原理是利用直流电场的电加热，电渗，电驱动和电泳等作用，即通过电动力学、电热学和电化学等的综合作用，有效地提高了采收率。文内介绍了该技术的现场应用情况，建立了物理模型，讨论了此技术的作用原理。     

隔井脉冲注水在提高油田采收率方面的应用

进入水驱后期，开采油田的剩余油高度分数，分流线和主流线的剩余油饱和度存在明显差别，运用水动力方法不断改变渗流场的流线分布是提高采收率的有效途径。常规脉冲注水（周期注水）显示了良好的运用前景，但是最佳参数难以把握，停注比过大引起地层能量过分下降，反而导致降水降液不增油，达不到预期的效果。     

微生物提高原油采收率的机理研究

实验中所选用的ＤＬＡ５、ＬＢ７、ＨＧ９细菌来自辽河油田、塔里木油田和江汉油田的油水样。用筛选培养出的３种细菌对青海七个泉油田的原油进行了处理，对毛细管等速电泳、气相色谱、红外光谱实测结果的分析表明，这３种细菌可降解青海七个泉油田原油的长链烷烃、芳烃支链，但对芳环骨架没有影响。代谢过程中产生有机酸、酯、酮类和气体等物质。有机酸主要是乙酸，气体主要是氮气。对微生物作用前后的原油物性进行测定，结果表明，微生物作用后可使原油粘度降低、蜡含量下降、凝固点降低。提高采收率是一种多因素协同作用的结果。     

利用水平井提高稠油油藏剩余油采收率技术

为了挖潜辽河油田A块超稠油油藏井间剩余油,应用数值模拟软件描述了水平井有利部署区温度场、压力场及剩余油分布:蒸汽吞吐周期较高的生产井周围油层动用情况较好,油层温度高达190～210℃,但蒸汽加热的有效面积只在井筒周围20～30 m,井间仍然有大部分区域处于45～65℃的低温状态;由于蒸汽吞吐过程中的汽窜现象,部分井之间有热连通形成.动用最好的区域油层压力为3.00 MPa,一般在3.40～3.90 MPa.井间存在大量剩余油,剩余油饱和度大于50%.在兴Ⅲ、兴Ⅱ_2油层单层厚度大干5 m区域整体部署水平井30口,水平段长度250～400 m.模拟预测水平井蒸汽吞吐8周期后,平均单井累计产油25 220 t,油汽比0.42,采出程度为31.5%.与直井生产效果对比,加密水平井可以挖潜稠油油藏井问剩余油,提高该区块采收率.图5表3参10     

抗垢碱提高稠油采收率机理研究

针对胜利油田夏八区块稠油油藏地层水钙镁离子浓度高,使用常规碱剂如氢氧化钠和碳酸钠等 进行驱油均会产生结垢问题,开展了具有抗垢作用的驱油用碱研究。 选用具有良好耐垢性能的偏硼酸钠 （NaBO2）进行了室内研究,并使用填砂管驱替实验评价了其驱油效果。 结果表明：虽然 NaBO2溶液降低油 水界面张力的效果不好,但其驱油效果较好。 驱替过程中,在较高的碱溶液浓度下出现了大的压差响应, 且提高采收率的幅度随着碱溶液浓度的增加而增大。 NaBO2溶液提高稠油采收率的微观机理为：碱溶液 易侵入原油中并形成分散液滴,这些液滴随即转变为 W/O 型乳状液,封堵高渗流通道,抑制黏性指进,从 而提高波及系数。     

聚合物驱后微生物提高采收率的可行性分析

胜利油区聚合物驱油藏的51．5％已经转入后续水驱阶段,如何进一步提高聚合物驱后的采收率,是油田面临的主要问题之一。结合微生物提高采收率的主要机理、聚合物驱后油藏的条件以及室内实验,以孤岛油田中一区Ng3单元为例,分析了聚合物驱后微生物提高采收率的可行性。结果表明,微生物具备进一步提高聚合物驱后油藏采收率的潜力,中一区Ng3物模实验可提高采收率7．8％～8．3％。     

致密油藏提高采收率技术瓶颈与发展策略

致密油藏正在成为全球油气资源勘探开发热点领域。致密油藏开发效益在一定程度上反映了一个国家当代石油勘探开发的技术能力和水平。总体来看,全球范围内致密油藏平均采收率为5%～10%,远低于常规油藏。中国致密油藏地质特征复杂,其开发关键技术尚处于突破前的准备阶段,美国相对成熟的致密油藏开发配套技术不能直接照搬应用。针对中国致密油藏采收率低和相关配套技术发展滞后的现状,概述了致密油藏开发和提高采收率的主要关键技术,剖析了待解决的理论认识与技术瓶颈等问题。分析认为,推行致密油藏开发地质工程、保护改造、增渗增能、洗油驱油"多维一体化"技术思路,协同大型水力压裂储层改造,实施界面修饰注水和储层原油氧化实现有效增能增注,开展多环节、多尺度、多场综合调控油水流动行为,显著增强油水流动能力,将是提高致密油藏采收率及开发综合效益的新途径。     

Y1砂砾岩低渗透油藏提高采收率对策研究

胜利油田Y1砂砾岩油藏投入开发后,由于地层能量下降,产能较低,长期处于低速低效开发状态。为提高油井产能,对该油藏重新进行了地质研究,通过精细地震解释、地层对比和测井储层评价,分析了Y1沙四段砂砾岩油藏注水受效特征,明确了注水受效的主要影响因素,合理优化了井网模式,确定了合理的井网密度及经济技术井距,提出了以多段压裂技术为主、径向水射流技术为辅、横向沟通储层、纵向均衡驱替的砂砾岩注采井网适配技术。这些技术实施后,该油藏产油量、采油速度、日注水量明显提高,含水率、注入压力下降,预测采收率可提高6.9%。     

新疆油田提高采收率问题的战略思考

该文对一次采油、二次采油、三次采油的开发阶段划分，对三次采油方法在中、低含水期相机“插入”而不是等到高含水期才用，提出了新的认识；对制约三次采油经济效益的因素，从战略角度进行了分析；对新疆油田提高采收率的方法提出了具体的建议。     

The application of nanofluids for recovery of asphaltenic oil

In the recent years, requirement of suitable enhanced oil recovery (EOR) technique as a more proficient technology becomes significant because of increasing demand for energy. Nanofluids have great potential in order to improve oil recovery. In our study, the effect of SiO₂, Al₂O₃, and MgO nanoparticles on oil recovery was investigated by using core flooding apparatus. Zeta potential and particle size distribution measurements were carried out to investigate the stability of nano particles and results showed SiO₂ has more stability than other ones. Interfacial tension and contact angle measurements between nanofluids and crude oil used to demonstrate that how nanoparticles enhance oil recovery. Experimental data reveals that SiO₂ nanoparticles introduce as the greatest agent among these nanoparticles for enhanced oil recovery. Lowest damage for SiO₂ nanofluids was observed and also it was observed that the concentration and injection rate have straight effects on permeability reductions.     

Microemulsion flooding for enhanced oil recovery

Petroleum recovery methods basically consist of fluid injection aiming to displace the oil out of the rock pores. Among the methods used in enhanced oil recovery, chemical methods, which may involve microemulsion flooding, are cited. In this work, injection assays have been carried out with two types of microemulsion: one was prepared with a commercial surfactant (MCS) and another contained a surfactant synthesized in laboratory (MLS). The experiments basically consisted of the injection of fluids into cylindrical plug samples from the Assu Formation (RN, Brazil). During the microemulsion flooding, samples were collected as a function of time and the mass of oil recovered by the microemulsion was determined. From the results obtained, one could conclude that the use of microemulsion prepared with the commercial MCS allowed for recovery indices as high as 87.5%, whilst the use of the MLS microemulsion permitted recovery indices as high as 78.7%. This was mainly due to the difference in viscosity between the two microemulsions used.     

Modelling of microbial enhanced oil recovery application using anaerobic gas-producing bacteria

Microbial enhanced oil recovery （MEOR） methods apply injection of bacteria to depleted oil reservoirs to produce oil, which had remained unrecovered after the conventional methods of production. The ability ofthermophilic anaerobic bacteria to produce gas as the main mechanism in potential MEOR in high salinities of 70-100 g/L was investigated in this study. Maximum gas production of up to 350 mL per 700 mL of salty solution was produced at a salinity of 90 g/L stably during 2-4 days of experiment. The experimental results were upscaled to the Snorre Oilfield, Norway, and simulated using ECLIPSE software for 27 months. The best scenarios showed that the increase in oil recovery on average was at 21% and 17.8% respectively. This study demonstrated that anaerobic bacteria used in biogas plants could be an attractive candidate for MEOR implementation due to their ability to withstand high temperature and salinity, and produce gas in large volumes.     

Enhanced heavy oil recovery and performance by application of catalytic in-situ combustion

Combustion tube experiments were carried out under various conditions to investigate the performance of catalytic in-situ combustion for recovering heavy oil. Compared with baseline experiment, the catalytic combustion exhibited better performance. Fractional oxygen gas in effluent gases was reduced by 2.9%, while fractional carbon dioxide and carbon monoxide was increased by 1.0% and 0.6%, respectively. Oxygen utilization efficiency was increased by 2.1% and apparent H/C atom ratio was lowered by 0.9%. The combustion performance was obtained under optimum experimental condition of air injection rate of 2.9?mL/min, preheated temperature of 190?°C, and grain-size gradation 2.