Oil Displacement Efficiency of Residual Oil after Polymer Flooding can be Enhanced by Betaine Surfactant

Because the oil is a kind of non-renewable resource, it is essential to enhance the oil recovery of the developed oil fields. Usually, as the remaining potential for exploitation of oil field after the secondary oil recovery is nearly 60% ~ 70%, so the tertiary recovery is always the subject of research for the petroleum experts around the world. Polymer flooding technology is successfully used in some oil fields such as Daqing oil field. Until now, the application of polymer flooding has been completed in some blocks. So how to exploit these reservoirs efficiently after polymer flooding is a challenge to the sustainable development of China´s oil industry. Through the microscopic oil-displacement experiment, the effect mechanism of residual oil in dead-end, prismatic residual oil and residual oil film on the channel wall after water flooding is studied by using a new amphoteric surfactant-betaine. The start-up and migration process and mechanisms of the kinds of residual oil are analyzed. The effect mechanism of the new amphoteric betaine surfactant on residual oil and the possibility of enhancing oil displacement efficiency after polymer flooding are studied.