Multifunctional Surfactant: Integration of Fracturing Fluid Flooding

Significant research focus has recently been directed toward energy-saving and emission-reduction practices, as well as the unique benefits of an integrated working fluid in the oilfield industry. Surfactants cannot be widely used in engineering practice due to cost constraints. At the same time, there is no proper solution to the flowback liquid problem. SY-JS, a multifunctional surfactant, was developed to broaden the application of surfactants in the oilfield industry. It still meets the field operation requirements of a good fracturing fluid thickener with a shear rate of 170 s-1 at 140�C and salinity (NaCl or KCl) of 12-13%. When the fracturing fluid has finished its job and returns to the ground, the molecular structure of the surfactant in the flowback fluid was found to be complete after laboratory evaluation of the fracturing and oil displacement integrated working fluid systems. Surfactants with an intact molecular structure should retain their distinct lipophilic and hydrophilic properties. When groundwater and produced water are compounded and re-injected into the reservoir for oil displacement, 0.2 percent anionic surfactant B1-12 is used to balance the charge and reduce interfacial tension. The rock`s contact angle can be reduced by 56.95 percent, and the recovery rate can be increased by 6%. Based on these findings, the surfactant`s dynamic self-healing mechanism was proposed. Furthermore, the capillary force, interfacial tension, and wettability were combined to propose wettability determines capillary force direction and interfacial tension determines capillary force magnitude. Furthermore, it provides favorable evidence that interfacial tension does not always reach ultralow levels during reservoir exploitation.