摘要
三元复合驱是进一步大幅度提高原油采收率的重要方法之一,目前已进入工业化推广阶段,但仍存在注采系统结垢及生产维护成本较高等问题。根据大庆油田三元复合驱的强碱、弱碱和无碱化战略部署,用氯化钠代替碳酸钠研发出无碱三元体系,但其乳化能力弱,采收率提高值比弱碱三元体系低2%~3%。为提高无碱三元体系的乳化性能,提升驱油效果,以无碱三元体系为基础,采用E表面活性剂与石油磺酸盐复配,研发出大庆油田无碱三元乳化驱油体系。体系不添加醇和助剂,且在表面活性剂质量分数较低(0.3%)时能够与大庆原油形成WinsorⅢ型中相微乳液。进一步研究表明,其增黏性、界面活性、黏度及界面张力稳定性、抗吸附性能与弱碱三元体系基本一致。驱油实验结果表明该体系具有注入能力强、色谱分离弱、乳化能力强的特点,可比水驱提高采收率41.12%,较弱碱三元体系增加提高采收率11.25%。根据室内研究结果,初步测算该体系吨油化学剂成本较弱碱三元体系下降42.90%。研发出的大庆油田无碱三元乳化驱油体系不仅实现了三元复合驱无碱化的目标,而且实现了从超低界面张力复合驱到低浓度中相微乳液驱的跨越,达到了大幅度提高采收率和降本增效的目的,具有广阔的应用前景,也可以为其他陆相砂岩老油田的高效开发提供技术借鉴。
Alkaline/surfactant/polymer(ASP)flooding is one of the important methods to further greatly improve oil recovery.Although this technique has put into industrial application,it still has problems such as scaling in injection and production system and high cost of production and maintenance.According to the strong alkali[sodium hydroxide(NaOH)],weak alkali[sodium carbonate(Na2CO3)]and alkali-free strategic plan made for ASP flooding in Daqing oilfield,alkali-free three-component system was developed by replacing sodium carbonate with sodium chloride.However,the emulsion performance of the system is weak,and oil recovery increment is 2%-3%OOIP lower than that of the weak alkali ASP flooding system.To improve the emulsion performance and enhance oil flooding effect,E-surfactant was compounded with petroleum sulfonate based on the alkali-free three-component system to develop the alkali-free three-component emulsification flooding system of Daqing oilfield.The system is free of alcohol and additives,and it can form Winsor typeⅢmiddle-phase micro-emulsion with Daqing crude oil when the surfactant mass fraction is low(0.3%).Further study shows that the thickening property,interfacial activity,viscosity,interfacial tension stability and anti-adsorption properties of the above system are basically the same as those of the weak alkali ASP flooding system.The core flooding experiment results show that the system is characterized by strong injectability,low degree of chromatographic separation,and good emulsion performance,which can improve oil recovery by 41.12%higher than water flooding and 11.25%higher than weak alkali ASP system.According to the results of laboratory study,the cost for chemical agent per ton of oil in this system was initially estimated to decrease by 42.9%compared with the weak alkali ASP flooding system.The alkali-free three-component system developed for Daqing oilfield not only achieves the alkali-free goal of three-component flooding,but makes a leap from ultra-low interfacial tension compound flooding to low-concentration middle-phase micro-emulsion flooding,which has reached the goal of largely improving oil recovery and decreasing cost and increasing efficiency.In fact,the system has a broad application prospect and can also provide technical reference for the efficient development of other old continental sandstone oilfields.
作者
程杰成
吴军政
吴昊
刘笑莹
何金钢
贾世华
Cheng Jiecheng;Wu Junzheng;Wu Hao;Liu Xiaoying;He Jingang;Jia Shihua(Daqing Oilfield Company Limited,Heilongjiang Daqing 163002,China;Key Laboratory of Enhanced Oil and Gas Recovery of the Ministry of Education,Northeast Petroleum University,Heilongjiang Daqing 163318,China)
出处
《石油学报》
EI
CAS
CSCD
北大核心
2023年第4期636-646,共11页
Acta Petrolei Sinica
基金
国家科技重大专项“大庆长垣特高含水油田提高采收率示范工程”(2016ZX05054)
国家自然科学基金项目(No.51674085)资助。
关键词
无碱三元驱油体系
E表面活性剂
中相乳状液
界面张力
乳化行为
alkali-free three-component flooding system
E-surfactant
middle-phase microemulsion
interfacial tension
emulsification behavior
作者简介
程杰成,男,1962年9月生,2000年获大连理工大学博士学位,现为中国工程院院士,主要从事油田提高采收率技术研究工作。Email:chengjiecheng@petrochina.com.cn;通讯作者:贾世华,男,1982年7月生,2005年获大庆石油学院学士学位,现为大庆油田有限责任公司高级工程师,主要从事油田提高采收率技术研究工作。Email:jiashihua@petrochina.com.cn。
