桩西原油/化学驱体系油水界面扩张流变性影响因素研究

Study on influence factors of oil-water interface dilatational rheological property of Zhuangxi crude oil/chemical flooding system

关键词:  化学驱  桩西原油  OP系列表面活性剂  扩张模量  弹性模量  黏性模量 

Key words:  chemical flooding  Zhuangxi crude oil  surfactant of OP series  dilatational modulus  elastic modulus  viscous modulus

摘要:

目前,化学驱技术是我国提高油田采收率的重要研究方向,而油水界面扩张流变性对于揭示化学驱的机理具有重要意义。为考察油水界面扩张流变性的影响因素,利用德国KRSS公司的DSA100型界面扩张流变仪对桩西原油/化学驱体系进行了研究。结果 表明:老化时间对油水界面扩张流变性具有显著影响；在桩西原油各组分中,沥青质组分对于油水界面扩张流变性的影响居于主导地位；油水体系的扩张模量和弹性模量会随着原油浓度的增大而先增大后减小,黏性模量的变化则不明显；油水界面的扩张模量和弹性模量随NaCl浓度的增大呈下降的趋势；OP系列表面活性剂会使体系的弹性模量减小,增大黏性模量的贡献,且OP系列表面活性剂的环氧乙烷数越多,作用效果越强。 

Abstract:

Chemical flooding technology is an important research direction in enhancing oil recovery. And oil-water interface dilatational rheology behavior plays a crucial role in revealing the mechanism of chemical flooding. In order to investigate the influence factors of dilatational rheology behavior of oil-water interface, dilational rheology behavior of Zhuangxi crude oil-water interface was investigated by DSA100 interfacial dilatational rheometer. The result showed that: aging time had significant effect on dilational rheological properties of oil-water interface； among fractions of Zhuangxi crude oil, asphaltene fraction had the most significant effect on oil-water interface dilational rheology; dilational modulus and elastic modulus of oil-water interface passed through distinct maxima as a function of Zhuangxi crude oil concentration, while changes of viscous modulus were not obvious; dilational modulus and elastic modulus of oil-water interface decreased with increase of NaCl concentration; after adding surfactants of OP series, elastic modulus would decrease and the contribution of viscous modulus on dilational modulus would increase, and the more epoxy ethane number of surfactants of OP series, the better the results.