界面性质表征二元驱驱油剂对采出液稳定性的影响

Influence of oil-displacing agent on stability of crude oil emulsions characterized by interfacial properties

关键词:  驱油剂  脱水率  界面张力  Zeta电位  稳定性 

Key words:  oil-displacing agent  dehydration rate  interfacial tension  Zeta potential  stability

摘要:

通过破乳脱水实验及界面性质研究了HPAM、吡咯林及其二元驱体系对原油乳状液稳定性的影响。实验结果表明:加入浓度为100 mg/L不同驱油剂后均使破乳剂BSE-238对原油乳状液的脱水率降低15%以上,SV值均增大,不同驱油剂均增强了原油乳状液的稳定性。含驱油剂的乳状液体系破乳后水相电导率增大、Zeta电位负值增大,破乳脱出水中含油量增大、油滴粒径减小。不同驱油剂影响乳状液稳定性的机理不同:HPAM对体系界面张力无明显影响,是通过增大体系黏度增强其稳定性；吡咯林对乳状液体系黏度无影响,大大降低油水界面张力而增强乳状液稳定性；两种驱油剂协同作用,使二元驱采出液更加稳定。 

Abstract:

The influence of HPAM, pyrrolin and pyrrolin/HPAM system on the stability of crude oil emulsion was studied through dehydration and interfacial properties experiment in this paper. The result indicated that when different oil-displacing agents with concentration of 100 mg/L were added in emulsion, the dehydration rate decreased by 15% and the SV value increased, the stability of crude oil emulsion was strengthened by all oil displacing agents. The conductivity and Zeta potential value of the water phase increased with demulsification, the median size of oil droplets decreased, then the coalescence of oil droplets was difficult. The stability mechanism of different oil-displacing agents was different:HPAM had no obvious influence on interfacial tension but made the emulsion stable by increasing its viscosity; however, pyrrolin greatly reduced the interfacial tension and had no influence on viscosity. The synergistic effects of the two oil-displacing agents made the emulsion more stable.