Comparison of a surfactant/polymer solution and its emulsion flowing in a porous medium
LIU Zheyu1,2, LI Yiqiang1,2, ZHUANG Yongtao3, CHEN Yihang4, MA Ruicheng4
1 College of Petroleum Engineering, China University of Petroleum-Beijing, Beijing 102249, China 2 State Key Laboratory of Petroleum Engineering, China University of Petroleum-Beijing, Beijing 102249, China 3 Oil Production Technology Institute, Dagang Oilfield Company, Tianjin 300280,China 4 Research Institute of EOR, China University of Petroleum-Beijing, Beijing 102249, China
The emulsion generated during combination flooding has a big impact on oil recovery. Unfortunately, there has been a lack of emulsion flow research. Core flow experiments were used to investigate the flow difference between oil in water emulsion and surfactant/polymer solution, which have the same viscosity by measuring pressure, rheological properties, particle size distribution and emulsion droplet morphology of the effluent. Meanwhile, surfactant polymer (SP) solution and oil was co-injected into a core to generate an emulsion. Impacts on emulsion flow properties, such as oil water ratio, surfactant concentration and flow velocity were investigated by comparing pressure curves. The results showed that there were significant flow differences between the SP solution and its generated emulsion. The pressure of the SP solution quickly achieved a steady level. However, the emulsion showed jamming and drop breakup phenomena. The rheology of the emulsion was not only shear thinning, but also shear thickening because pore throat shearing increased its dispersion. The analysis of effluent indicated that as the viscosity of the emulsion increased, the droplet size decreased and the emulsion morphology become similar to its initial status after 3PV. The surfactant concentration has more effect than shear rate on the emulsification, while the oil saturation has a minimal effect.
surfactant/polymer flooding emulsion percolation rule rheology porous medium
刘哲宇，李宜强，庄永涛，陈一航，马瑞程. 多孔介质中二元复合体系乳化前后流动规律研究[J]. 石油科学通报, 2017, 2(4): 527-535. LIU Zheyu, LI Yiqiang, ZHUANG Yongtao, CHEN Yihang, MA Ruicheng. Comparison of a surfactant/polymer solution and its emulsion flowing in a porous medium. Petroleum Science Bulletin, 2017, 2(4): 527-535.