The Effect of Following Water after Polymer Flooding on the Displacement Efficiency with Alternately Injecting Slug of Gel and Polymer/Surfactant

Aiming at the development of remaining oil after polymer flooding, the author develops an oil displacement technology, alternately injecting the slug of the gel and polymer/surfactant compound system, which can advanced improve the remained oil after polymer flooding. By using the artificial large flat-panel model, the oil displacement experiments are carried on to study the injection characteristics and the displacement efficiency of the alternately injecting the slug of gel and polymer/surfactant compound system, and whether the following water should be injected after polymer flooding has been discussed. The experimental results show that, the recovery of alternately injecting the gel and polymer/surfactant slug after polymer flooding could enhance recovery more than 10% on the basis of polymer flooding, the following water after polymer flooding has a little impact on the final recovery but increasing time and the difficulty of development. Therefore, these results provide the technology that alternately injecting the slug of the gel and polymer/surfactant could advance develop the residual oil and enhance the recovery after polymer flooding.