SSRN Electronic Journal | 2021
The Reservoir Adaptability Evaluation and Oil Displacement Mechanism of a Novel Particle-Type Polymer Flooding Technology
Abstract
In recent years, a series of field tests of a novel particle-type polymer (named self-adaptive microgel) flooding technology have been carried out in different oilfields. However, compared with its field application, the research on its performance evaluation and oil displacement mechanism is still in the initial stage. Therefore, this paper made a profound study on its physicochemical properties, reservoir adaptability, transport and deep fluid diversion ability, oil displacement mechanism and the further EOR effect after polymer flooding. Results show that, during its injection process, the particle phase separation phenomenon occurs. So it would plug large pores while leave small ones open, causing no damage to the low permeability layer. Therefore, microgel particles gather in the larger pore to form bridge blocking, and its carrier fluid displace oil in the small pore. Working in cooperation, self-adaptive microgel can realize deep fluid diversion, expand macroscopic and microscopic swept volume. Furthermore, when migrating in the porous media, it shows the motion feature of “trapping, deformation, migration, re-trapping, re-deformation and re-migration”. On this basis, the displacement experiments show that, the combination of self-adaptive microgel flooding with well pattern adjustment, is an effective way to further enhance oil recovery significantly after polymer flooding.